These units are wrong.
M is roman numeral for 1000, and does not mean a million, unless using the SI system. For representing a million BTU in the IP system the abbreviation is MMBTU. Technically, this chart units are 1000 BTU, but the data is actually million.
Additionally KBTU/HR is not an IP unit. The correct units are MBH (pronounced one thousand BTUs per hour). k=kilo in the metric system.
I've been a mechanical engineer for 23 years. This is factual information that is used by industry. What will it take to fix this?