The 142008 is to be expected. The page has 71003 code points, 2 bytes per code point (I guess that zh.wikipedia.org is simplified Chinese and normally only uses

The 142008 is to be expected. The page has 71003 code points, 2 bytes per code point (I guess that zh.wikipedia.org is simplified Chinese and normally only uses characters from the BMP) gives 142006 bytes. I'd guess that the two remaining bytes are the byte order mark.