Stefanie Leimeister. IT Outsourcing Governance

Transcription

1 Stefanie Leimeister IT Outsourcing Governance

2 GABLER RESEARCH Informationsmanagement und Computer Aided Team Herausgegeben von Professor Dr. Helmut Krcmar Die Schriftenreihe präsentiert Ergebnisse der betriebswirtschaft lichen Forschung im Themenfeld der Wirtschaftsinformatik. Das Zusammenwirken von Informationsund Kommunikationstechnologien mit Wettbewerb, Organisation und Menschen wird von umfassenden Änderungen gekennzeichnet. Die Schriftenreihe greift diese Fragen auf und stellt neue Erkenntnisse aus Theorie und Praxis sowie anwendungsorientierte Konzepte und Modelle zur Diskussion.

3 Stefanie Leimeister IT Outsourcing Governance Client Types and Their Management Strategies With a foreword by Prof. Dr. Helmut Krcmar RESEARCH

4 Bibliographic information published by the Deutsche Nationalbibliothek The Deutsche Nationalbibliothek lists this publication in the Deutsche Nationalbibliografie; detailed bibliographic data are available in the Internet at Dissertation Technische Universität München, st Edition 2010 All rights reserved Gabler Verlag Springer Fachmedien Wiesbaden GmbH 2010 Editorial Office: Ute Wrasmann Anita Wilke Gabler Verlag is a brand of Springer Fachmedien. Springer Fachmedien is part of Springer Science+Business Media. No part of this publication may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the copyright holder. Registered and/or industrial names, trade names, trade descriptions etc. cited in this publication are part of the law for trade-mark protection and may not be used free in any form or by any means even if this is not specifically marked. Coverdesign: KünkelLopka Medienentwicklung, Heidelberg Printed on acid-free paper Printed in Germany ISBN

5 Foreword Information systems (IS) outsourcing is a key driver as well as an outcome of the professionalization, industrialization, and service orientation in the IT services industry. It has become an established business practice and a popular research issue. Along with this popularity, outsourcing has changed tremendously over the past decades and so have its scope, complexity, and the variety of outsourcing options. Surprisingly, still many outsourcing arrangements are not successful. Divergent expectations of both parties towards the venture along with an insufficient governance can cause the outsourcing relationship to turn sour. Current research shows that a one-size-fits-all governance approach for outsourcing projects is not appropriate and a differentiation of outsourcing clients is necessary. Encouraged by the current challenges of the outsourcing market, this work presents a differentiated approach to investigate various types of IS outsourcing relationships and their characteristics depending on the underlying expectations of the outsourcing clients. Grounded on the current body of knowledge of the outsourcing research literature and a variety of current theories in the fields of information systems, business administration, and social theories, it develops a framework for classifying outsourcing projects and clients. This framework builds the foundation to empirically examine different outsourcing projects, their constitutive elements, and management approaches among German IT executives and CIOs. Based on these insights, the work proposes appropriate governance mechanisms for the management of each outsourcing client type. Stefanie Leimeister s work shows that outsourcing endeavors should be linked to the needs and expectations of their stakeholders, both on the client and on the vendor side. She clearly depicts that outsourcing governance goes beyond contractual issues. It has to consider various management aspects in order to shape a successful long-term outsourcing venture. This work is an important contribution to the research field of managing information systems. In a methodological way it gives valuable impulses for combining different theories and research methods depending on the actual context of an outsourcing arrangement. The work appeals by its broad scope of theory, multimethodological background and approaches, and its comprehensive argumentation by which literature and empirical findings are presented. Researchers of information systems will gain new insights on which research methods and theories are applicable given the motivation of the stakeholders to engage in an outsourcing endeavor. For practitioners, it provides recommendations for orchestrating the development of a healthy outsourcing relationship and for effectively and efficiently allocating resources. I recommend this book as a valuable reading and resource. It provides new and promising insights into an established research field and inspires different kinds of readers to adopt a new perspective on make-or-buy decisions in information systems. I hope this work will find the broad dissemination and attention it deserves. Prof. Dr. Helmut Krcmar

6 Acknowledgements From the beginning of my academic career to the final version of this book more than five years have passed. Those who have completed this journey understand that there are so many people to thank for contributing to this work and supporting me. I would like to express my gratitude to everyone involved I appreciated and enjoyed every minute of their time. Thank you to my doctoral advisor Prof. Dr. Helmut Krcmar for his continuous support, his trust and the freedom he gave me to unfold my ideas and personality, and his transition from an instructor to a mentor to Prof. Dr. Florian von Wangenheim for accepting to be my second doctoral advisor and providing me with valuable input for the methodological and statistical part of this work to Prof. Dr. Phillip Yetton and Joan Spiller for their interest in my work and me and their unobtrusive stimulation towards academic brilliance to Prof. Dr. Marilyn Tremaine and Prof. Dr. Scott Tremaine who inspired me to think outside the box, to modestly question established things, who shared their joy for Canada with me and became good friends to Prof. Dr. Tilo Böhmann who ignited the initial thoughts towards the final thesis topic, for supporting and accompanying me in my academic career from being his graduate assistant to the doctor s degree to Dr. Holger Hoffmann, Uta Knebel, Dr. Michael Schermann, and Cathleen Stephan for sharing the joy and burden of our work life, inspiring my thoughts, and their transition from colleagues to good friends to Dr. Holger Jehle for broadening my horizons, inspiring my curiosity, and for his time to Stefanie Hammer and Tina Kopf for being my best friends and believing in me to Martin for being my big brother and soul mate to Marco for his love The deepest appreciation and gratitude goes to my parents who instilled in me a love of reading, writing, and learning. They encouraged and supported my ideas and believed in what I did even if it was not their way of thinking. Thank you for your unquestioned love, trust, and patience. Stefanie Leimeister

7 Abstract Problem Situation and Motivation: The outsourcing of information systems has been a wide-spread management practice for several decades and has been a popular research issue since then. Surprisingly, despite the experience with IS outsourcing, numerous outsourcing arrangements are renegotiated or even terminated. Likely reasons for such failures can be ascribed to divergent expectations of both parties towards the venture and an insufficient governance of the outsourcing relationship. Current research shows that a one-size-fits-all governance approach for all outsourcing projects regardless of the underlying outsourcing motivation is not appropriate. A differentiation of outsourcing clients and the configuration of their venture is needed. Purpose: The objective of this thesis is to explore and understand different types of IS outsourcing relationships and their configuration depending on the underlying expectations of the outsourcing clients. Furthermore, appropriate governance mechanisms for the successful management of IS outsourcing relationships are to be identified for each client type. The thesis will answer the following three research questions: 1) What are the constitutive elements of a client-vendor relationship in IS outsourcing? 2) Which different configurations of outsourcing relationships can be identified empirically? 3) What are appropriate governance approaches and mechanisms for the successful management of different outsourcing relationships? Research Design and Methodology: This work applies a multi-method approach and triangulates results from various qualitative and quantitative methods. Preceding the main study, an extensive qualitative pre-study is conducted with 18 expert interviews from both the client and vendor side. For the main study, an empirical-quantitative, but exploratory approach is chosen. Data is collected from the client perspective, i.e., IT managers and Chief Information Officers, through an online survey, resulting in 268 data points. The data is analyzed with cluster analysis to identify homogeneous groups of outsourcing clients. Group differences are examined with analyses of variance (ANOVA). Then a governance model is developed to examine different governance approaches (determinants) and their effects on outsourcing performance for each client group. This model is tested with Partial Least Square (PLS) structural equation modeling and multi-group comparisons (t-tests). Findings: Four predominant outsourcing motives are identified: Cost-focused, businessoriented, strategy-focused, and IT-related motives. A cluster analysis along these outsourcing motives reveal four client groups with different and very focused expectations: 1) businessefficiency clients, 2) cost-conscious smart shoppers, 3) strategists and innovation seekers, and 3) IT excellence and reliability-oriented clients. Three client groups have very straightforward expectations focused on only one category of outsourcing motives (e.g., cost focus), while clients in group 4 have heterogeneous motives, expecting both business and IT motives. In terms of governance approaches, the business-efficiency clients manage their outsourcing venture via management processes and relational governance; cost-focused clients govern via the contract and staff experience; the strategy-oriented group uses the contract and relationship management as primary governance modes. Surprisingly, for the heterogeneous last group none of the established and tested governance modes works appropriately. Rather, ven-

8 X Abstract dor flexibility seems to be a promising management approach for this group. Each group establishes different governance approaches that lead to a successful overall outsourcing performance. Contributions to Theory: In contrast to prior research, this thesis adopts a more differentiated perspective on outsourcing by examining unique outsourcing client types and linking clients outsourcing expectations with appropriate governance approaches. It applies and confirms common theories such as transaction cost economics and social exchange theories by clarifying key outsourcing motives and by deriving a framework with characteristics of outsourcing relationships. It also extends these theories by applying them depending on the context (i.e., underlying motive structure) of the venture and stating which theories on governance approaches are most appropriate to explain outsourcing performance depending on the underlying expectations. Based on the results, governance determinants of outsourcing success can be better predicted depending on the context of client expectations. Contributions to Practice: The results of this work help IT decision makers to get a clear understanding about the primary underlying motivations of clients to engage into an outsourcing venture. Building upon an informed decision, characteristics of other outsourcing ventures with similar expectations can be benchmarked against the characteristics of their own venture. A specialized governance concept for each of the identified groups is required for a successful management of the different configurations of outsourcing relationships. This will provide IT decision makers with workable strategies for successfully governing different outsourcing projects. It eventually helps to effectively and efficiently allocate the appropriate economic and human resources for the outsourcing venture. Research Limitations / Further Research: Methodological constraints of the work comprise some known weaknesses of the multivariate method of cluster analysis. Especially, group sizes suggested by the chosen cluster algorithm do not necessarily reflect the client population in reality. Also, only single-source data is used that is collected at one point in time. This might increase a potential common method bias (CMB), although the analysis shows that CMB does not impact the results. Concerning the object of inquiry, a consideration of the vendor perspective could provide fruitful insights and contrast mutual expectations towards an outsourcing relationship. Keywords: IS outsourcing, governance, relationship management, formal contract, factor analysis, cluster analysis, structural equation modeling, partial least squares, SEM, PLS.

9 Table of Contents Foreword... V Acknowledgements... VII Abstract... IX Table of Contents... XI List of Figures... XVII List of Tables... XXI List of Abbreviations... XXV Introduction... 1 Problem Statement and Motivation for this Research... 1 Research Objective and Research Questions... 3 Outline and Structure of the Thesis... 6 Epistemological Foundation and Research Methodology... 9 Philosophical Perspectives and Research Epistemology Positivist Research Interpretive Research Critical Research Research Design and Methods: Quantitative vs. Qualitative Research Summary of Epistemological Foundations of this Thesis Theoretical Background on Outsourcing Definition and Background of Information Systems Outsourcing Specific Characteristics of Information Systems Outsourcing IS Outsourcing Definitions Theoretical Foundation: Related Theories Transaction Cost Economics Exchange Theories: Social Exchange and Relational Exchange Theory Social Exchange Theory Relational Exchange Theory Psychological Contract Theory... 26

10 XII Table of Contents Expectation Confirmation Theory Theories of Power: Power-Political, Power Dependence, Power Conflict Summary of Theories for IS Outsourcing Relationships The Multi-Dimensionality of Outsourcing IS Functions Outsourcing Functions and the IT Service Lifecycle Forms of Outsourcing Arrangements Outsourcing Determinants and Expectations: Advantages and Disadvantages 39 Prior Research on IS Outsourcing Relationships: State of the Art Evolution of IS Outsourcing Research towards a Relationship Focus The Relationship Perspective in IS Outsourcing Approaches for Classifying IS Outsourcing Relationships Constitutive Factors of an IS Outsourcing Relationship Strategic Intent and Contextual Factors Relationship Architecture Governance and Monitoring Mechanisms Formal Contractual Governance Informal Relational Governance The Interplay of Formal Contractual and Informal Relational Governance Governance via Management Processes Governance via Organizational Structures Governance via Experience and Risk-Reward Incentive Mechanisms Relational and Behavioral Interactions of the Outsourcing Parties Success of IS Outsourcing Shortcomings of the Current Research / Research Gap on Outsourcing Relationships and their Governance Framework for Classifying Outsourcing Relationships Methodological Approach to the Conceptualization of a Framework on Outsourcing Relationships Categories of the Framework Completeness vs. Parsimony of the Building Blocks Interdependencies among the Variables Conceptual Framework for Types in IS Outsourcing Relationships Summary of Outsourcing Foundations Theoretical and Methodological Foundations for Classifying Data Theoretical Foundations of Classification and Configuration Definition of Classification Terms: Classification, Configuration, Type Characteristics of Configurations or Types Typologies vs. Taxonomies Grouping Techniques... 86

11 Table of Contents XIII Cluster Analysis Definition of Cluster Analysis General Procedure of Cluster Analysis Different Clustering Techniques and Algorithms Clustering Steps Strengths and Pitfalls of Cluster Analysis Discriminant Analysis Factor Analysis General Considerations and Distinctions in Factor Analysis: Exploratory vs. Confirmatory, R vs. Q Analysis Design and Process of a Factor Analysis Summary of the Methodological Foundations for Classifying Outsourcing Clients Empirical Evidence of Outsourcing Relationship Types Qualitative Pre-Study: First Evidence of Different IS Outsourcing Relationships Data Collection Results Strategic Intent, Expectations, and Context Relationship Architecture Governance and Monitoring Interaction Types of IS Outsourcing Relationships Research Design of the Quantitative Study Data Collection and Demographic Results Statistical Results: Data Analysis Diagnostic Pre-Analysis of Results: Missing Values and Distribution of Data Diagnostics: Analyzing the Extent and Impact of Missing Values Normal Distribution of the Data Factor Analysis: Customer Expectations towards IS Outsourcing Initial Factor Analysis with All Outsourcing Motives Final Improved Factor Solution Reliability Analysis of the Final Factor Solution Interpretation of Factors Cluster Analysis: Finding Configurations of Clients with Similar Outsourcing Expectations Selecting and Preparing the Input Variables for the Cluster Analysis Identifying Outliers in the Data Set Identifying the Number of Clusters and the Cluster Centroids Optimizing the Cluster Solution with k-means Estimating and Validating the Cluster Solution with Discriminant Analysis

12 XIV Table of Contents 5.5 Interpretation of Statistical Analysis: Configurations of Different Outsourcing Client Groups Constitutive Elements of the Client Configurations: Major Outsourcing Expectations and Strategic Intents Context Factors Basic Company Characteristics Role and Impact of IT for the Company Relational Architecture of the Outsourcing Ventures Experience with Outsourcing Outsourcing Objects and Degree of Outsourced Functions Number of Involved Vendors: Single vs. Multi-Vendor Outsourcing Outsourcing Degree: Selective vs. Total Outsourcing Length and Duration of Outsourcing Contracts Pricing Arrangements for Outsourced Services Outsourcing Alliances Dependency on the Service Provider and Switching Costs Goal Alignment between Outsourcing Parties Governance Approaches among the Different Client Groups Outsourcing Governance: Role of the Contract Outsourcing Governance: Role of Processes Outsourcing Governance: Role of Structures and Structural Liaison Devices Outsourcing Governance: Informal Relationship The Role of Staff Experience, Degrees of Freedom for the Vendor, and Risk-Reward Mechanisms as Governance Mechanisms Interactions: Role of Specific Relationship Factors Communication Conflict Resolution and Consensus Cooperation and Coordination Commitment and Loyalty Cultural Similarity Trust Vendor Flexibility Vendor Proactivity Outsourcing Success: Perceived Service Quality and Satisfaction Summary and Consolidated Description of the Four Client Configurations Governance of IS Outsourcing Relationship Types Research Design: Governance Model and Construct Development Research Approach and Validation Model Validation and Results Formative Measurement Model Reflective Measurement Model

13 Table of Contents XV Structural Model Group Analysis: The Impact of Different Governance Mechanisms among the Four Client Groups Mediating Effects in the Model Assessment of Common Method Bias Discussion and Interpretation of Results Conclusion and Outlook on Future Research Results and Contributions to Theory Results and Contributions to Practice Main Research Limitations Outlook on Future Research References Appendix

14 List of Figures Figure 1-1. Work structure and analytical index of the thesis... 7 Figure 3-1. Outsourcing functions and the IT service lifecycle Figure 3-2. Dimensions of outsourcing options Figure 3-3. Evolution of outsourcing research issues Figure 3-4. Classification scheme of IS outsourcing governance approaches Figure 3-5. Overview of conceptual framework for IS outsourcing relationship types Figure 4-1. Different clustering technique approaches Figure 5-1. Phases of the quantitative research process Figure 5-2. Anecdotal types of different IS outsourcing relationships Figure 5-3. Combination of methods applied in this thesis Figure 5-4. Distribution of industries in the overall sample Figure 5-5. Distribution of the annual sales volume of respondent companies in the overall sample Figure 5-6. Visual solution using the Cattell s scree plot (final factor solution) Figure 5-7. Estimating the number of clusters via the elbow criterion Figure 5-8. Distribution and cluster size of the four configurations Figure 5-9. Overview of cluster profiles with regard to outsourcing expectations Figure Mean factor scores for factor innovation and strategy expectations Figure Mean factor scores for factor technology expectations Figure Mean factor scores for factor business expectations Figure Mean factor scores for factor cost expectations Figure Overview of detailed outsourcing expectations (mean values) among the four configurations Figure Group means for the average perceived importance of IT for the company among the four client configurations

15 XVIII List of Figures Figure Group means for average effort / degree of switching costs to another service provider among the four client configurations Figure Degree of complementarity of goals among the four client configurations Figure Degree of conflicts of interest among the four client configurations Figure Easiness of task specification and governance via the contract among the four client configurations Figure Sufficiency of contract for outsourcing governance among the four client configurations Figure Degree of established SLA and contract management processes among the four client configurations Figure Degree of established performance and service measurement processes among the four client configurations Figure Degree of established strategy processes among the four client configurations Figure Degree of established benchmarking processes among the four client configurations Figure Establishment of a management board among the four client configurations Figure Establishment of a relationship manager among the four client configurations181 Figure Establishment of an external consultant among the four client configurations 181 Figure Degree / importance of personal bonds between employees and teams among the four client configurations Figure Degree of informal vs. formal relationship among the four client configurations Figure Importance of relationship management for outsourcing venture among the four client configurations Figure Degree of long-term client experience with the specific vendor among the four client configurations Figure Degree of perceived know-how and experience of the client to control vendor among the four client configurations Figure Degree of freedom attributed to the vendor for planning, developing, and running client IT among the four client configurations

16 List of Figures XIX Figure Degree of involvement of the vendor in management issues of the client among the four client configurations Figure Degree of risk and reward share between client and vendor among the four client configurations Figure Degree of communication among the four client configurations Figure Degree of conflict resolution potential between client and vendor among the four client configurations Figure Degree of consensus between client and vendor among the four client configurations Figure Degree of coordination between client and vendor among the four client configurations Figure Degree of cooperation between client and vendor among the four client configurations Figure Degree of loyalty and commitment between client and vendor among the four client configurations Figure Degree of understanding the culture of the other party among the four client configurations Figure Degree of cultural similarity of both parties among the four client configurations Figure Importance of trust between the parties among the four client configurations. 197 Figure Degree of trust between the parties among the four client configurations Figure Degree of flexibility of the vendor among the four client configurations Figure Degree of proactivity and suggestions for innovation potential of the vendor among the four client configurations Figure Overall satisfaction with outsourcing among the four client configurations Figure Degree of perceived service quality of the outsourced services among the four client configurations Figure Differences between expected and achieved benefits of outsourcing among the four client configurations Figure Schematic overview and comparison of five qualitatively derived and four quantitatively derived outsourcing client types

17 XX List of Figures Figure 6-1. Governance research model Figure 6-2. Structural model findings in the overall sample Figure 6-3. Structural model findings in group Figure 6-4. Structural model findings in group Figure 6-5. Structural model findings in group Figure 6-6. Structural model findings in group

18 List of Tables Table 3-1. Table 3-2. Table 3-3. Table 3-4. Table 3-5. Table 3-6. Table 4-1. Table 4-2. Table 4-3. Table 4-4. Table 4-5. Table 4-6. Table 5-1. Table 5-2. Table 5-3. Table 5-4: Table 5-5. Table 5-6. Table 5-7. Table 5-8. Table 5-9. Definitions of information systems outsourcing Overview of theoretical foundations applied in this thesis Compilation of outsourcing motives Compilation of relationship factors in the literature Exemplary definitions of IS outsourcing outcomes and success Categories of conceptual framework for IS outsourcing relationship types Basis of cluster analysis: score (S) matrix of objects and variables Distance measures in cluster analysis Common cluster algorithms for defining multi-member cluster similarity Requirements for the level of measurement of different methods of dependency measures Rules of thumb for assessing the appropriate sample size for factor analysis Evaluation thresholds of KMO values Overview of expert interviews Variety of IS outsourcing expectations included in the study Correlation matrix of involved variables (final factor solution) KMO and Bartlett s test (final factor solution) Communalities of initial and extracted factor solution (final factor solution) Extraction of factors and total variance explained (final factor solution) Rotated component matrix (final factor solution) Reproduced correlation matrix and residuals (final factor solution) Reliability / internal consistency of the factor scales Table Interpretation of identified factors Table Changes in the heterogeneity coefficient of the Ward clustering algorithm

19 XXII List of Tables Table Mean values of 4-cluster solution for clustering variables with Ward / initial cluster centroids Table Mean values of final 4-cluster solution for clustering variables with k-means 147 Table Constitutive outsourcing expectations of the four client configurations Table Relation between industry and client configurations (residuals between observed and expected frequencies; percentages of distribution) Table Distribution of annual sales among the four client configurations (residuals and percentage of distribution) Table Distribution of company size (number of employees) among the four client configurations (residuals and percentage of distribution) Table Distribution of IT budget among the four client configurations (residuals and percentage of distribution) Table Experience with outsourcing among the four client configurations Table Outsourced functions among the four client configurations: business processes Table Outsourced functions among the four client configurations: IT applications Table Outsourced functions among the four client configurations: IT infrastructure 165 Table Number of outsourcing vendors among the four client configurations Table Degree of outsourcing among the four client configurations Table Duration of the current outsourcing contract among the four client configurations Table Dominant pricing arrangements among the four client configurations Table Outsourcing alliance models among the four client configurations Table Outsourcing relationship types framework: overview of four client groups and their characteristics Table 6-1. Table 6-2. Table 6-3. Table 6-4. Construct measurement Indicator and construct reliability for group data samples and overall sample 223 PLS crossloadings of reflectively measured constructs for group sample PLS crossloadings of reflectively measured constructs for group sample

20 List of Tables XXIII Table 6-5. Table 6-6. Table 6-7. Table 6-8. Table 6-9. PLS crossloadings of reflectively measured constructs for group sample PLS crossloadings of reflectively measured constructs for group sample PLS crossloadings of reflectively measured constructs for overall sample f² effect size values for all four client groups PLS multi-group comparison of structural model: t-values and level of significance for group differences between the four client groups Table Summary of potential sources of common method biases

21 List of Abbreviations ASP AMOS ANOVA AVE B2B BPO CA CAGR CFA CFO CIO CMB CMV CR EFA et seq. FA ff. IS ISR ITO KMO LISREL MAR Application Service Provider Analysis of Moment Structures Analysis of Variance Average Variance Extracted Business to Business Business Process Outsourcing Cluster Analysis Compound Annual Growth Rate Confirmatory Factor Analysis Chief Financial Officer Chief Information Officer Common Method Bias Common Method Variance Composite Reliability Exploratory Factor Analysis et sequentes; and following (pages) Factor Analysis, often used synonymously to PAF or PFA and following pages Information Systems Information Systems Research IT Outsourcing Kaiser-Meyer-Olkin Measure of Sampling Adequacy Linear Structural Relations Missing at Random

22 XXVI List of Abbreviations MCAR MDA MLE MSA PCA PAF PFA PLS RET SAHN SD SET SEM SLA S-N-K SPSS StD TCE VAF VIF Missing Completely at Random Multivariate Discriminant Analysis Maximum Likelihood Estimation Measure of Sampling Adequacy Principal Component Analysis Principal Axis Factoring, also known as Principal Factor Analysis or Common Factor Analysis Principal Factor Analysis, also known as Principal Axis Factoring or Common Factor Analysis, sometimes only abbreviated as FA Partial Least Squares Relational Exchange Theory Sequential, Agglomerative, Hierarchical and Non-overlapping Standard Deviation Social Exchange Theory Structural Equation Model Service Level Agreement Student-Newman-Keuls Test (non-parametric post-hoc test) Statistical Package for the Social Sciences Standard Deviation Transaction Cost Economics Variance Accounted For Variance Inflation Factor