INVENTORY PLANNING WITH FORECASTING EXPENDITURE Sanjay Sharma Inventory Planning with Forecasting Expenditure Inventory Planning with Forecasting Expenditure Sanjay Sharma First edition published 2022 by CRC Press 6000 Broken Sound Parkway NW, Suite 300, Boca Raton, FL 33487-2742 and by CRC Press 4 Park Square, Milton Park, Abingdon, Oxon, OX14 4RN © 2022 Sanjay Sharma First edition published by CRC Press 2022 CRC Press is an imprint of Taylor & Francis Group, LLC Reasonable efforts have been made to publish reliable data and information, but the author and publisher cannot assume responsibility for the validity of all materials or the consequences of their use. The authors and publishers have attempted to trace the copyright holders of all material reproduced in this publication and apologize to copyright holders if permission to publish in this form has not been obtained. If any copyright material has not been acknowledged please write and let us know so we may rectify in any future reprint. Except as permitted under U.S. Copyright Law, no part of this book may be reprinted, reproduced, transmitted, or utilized in any form by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying, microfilming, and recording, or in any information storage or retrieval system, without written permission from the publishers. For permission to photocopy or use material electronically from this work, access www.copyright.com or contact the Copyright Clearance Center, Inc. (CCC), 222 Rosewood Drive, Danvers, MA 01923, 978-750-8400. For works that are not available on CCC please contact [email protected] Trademark notice: Product or corporate names may be trademarks or registered trademarks and are used only for identification and explanation without intent to infringe. ISBN: 978-1-032-20929-6 (hbk) ISBN: 978-1-032-21202-9 (pbk) ISBN: 978-1-003-26725-6 (ebk) DOI: 10.1201/9781003267256 Typeset in Times by MPS Limited, Dehradun Contents Preface......................................................................................................................vii Author.......................................................................................................................ix Chapter 1 Introduction..........................................................................................1 1.1 Planned Schedule......................................................................1 1.2 Problem Description.................................................................4 1.3 Forecasting Expenditure...........................................................4 1.3.1 For Buying...................................................................5 1.3.2 For Making................................................................11 1.4 Potential Benefit......................................................................22 Chapter 2 Procurement.......................................................................................25 2.1 Cost Estimate..........................................................................25 2.2 Modified Cost Estimate..........................................................25 2.3 Related Index..........................................................................27 2.4 Analysis...................................................................................30 2.4.1 Reduction in the Forecasting Expenditure...............30 2.4.2 Increase in the Forecasting Expenditure..................31 2.5 Threshold Value......................................................................36 2.5.1 Ordering Cost Variation............................................36 2.5.2 Carrying Cost Variation............................................38 Chapter 3 Production..........................................................................................55 3.1 Total Cost Formulation..........................................................55 3.2 Modified Total Cost................................................................55 3.3 Relevant Index........................................................................56 3.4 Effects.....................................................................................59 3.4.1 Decrease in the Forecasting Expenditure.................59 3.4.2 Raise in the Forecasting Expenditure.......................60 3.5 Influence on R Value..............................................................65 3.5.1 Facility Setup Cost....................................................65 3.5.2 Holding Cost..............................................................66 Chapter 4 Applications.......................................................................................85 4.1 Buying.....................................................................................85 4.2 Making....................................................................................87 4.3 Associated Index.....................................................................90 4.3.1 Buying........................................................................90 4.3.2 Making.......................................................................96 v vi Contents 4.4 Influence................................................................................101 4.4.1 Purchase...................................................................102 4.4.2 Production................................................................106 Chapter 5 Highlights........................................................................................113 5.1 Cost of Forecasting...............................................................115 5.2 Evolution Stage.....................................................................116 5.3 Business Use.........................................................................126 Appendix...............................................................................................................129 General Reading..................................................................................................183 Index......................................................................................................................209 Preface In an industrial or business case, purchase or procurement is a significant function. Usually a procurement plan is prepared on the basis of a certain prediction of consumption pattern or demand. However when this plan is implemented, then the desired benefit is obtained corresponding to the forecast accuracy. In the available literature, the forecasting accuracy is discussed a lot. A need is established to link the forecasting accuracy with a forecasting expenditure. After an explicit inclusion of the forecasting expenditure, the inventory planning for procurement/production is described in the present book. This book is expected to be useful for UG/PG students in engineering and management and also has good potential for elective/supplementary core courses. Sanjay Sharma Mumbai, India vii Author Sanjay Sharma is a professor at the National Institute of Industrial Engineering (NITIE), Mumbai, India. He is an operations and supply chain management educator and researcher with more than three decades of experience, including industrial, managerial, teaching and training, consultancy, and research. Professor Sharma has many awards and honors to his credit. He has published eight books and papers in various journals such as European Journal of Operational Research, International Journal of Production Economics, Computers & Operations Research, International Journal of Advanced Manufacturing Technology, Journal of the Operational Research Society, and Computers and Industrial Engineering. He is also on the editorial board of several journals, including the International Journal of Logistics Management. ix