XQ0901This report provides methods of calculating heating values of natural gas with different compositions. This revised version contains a program in Excel Spreadsheet for heating values and other related calculations, both in Imperial and SI units. The program in Excel is provided in a CD-ROM for purchasers of the Paper/CD-ROM and Print+PDF formats. Purchasers of the "Secure PDF" format will receive the program as downloadable supplemental files immediately after purchase.