The label of the ordinate contains an error - kilobyte = byte * 1024, as opposed to byte / 1024
#bytes * (1 kilobyte)/(1024 bytes) = #kilobytes
or bytes/1024=kilobytes, for short.
Basically, it's a conversion factor, not a definition.
http://en.wikipedia.org/wiki/Kibibyte
It is a tradeoff, it avoids the need to explain which definition of kilo is used, at the cost of using a far less common term.