output of vmstat

i have 2 question about vmstat

1)
pin (pagein) output of vmstat is always zero for our system
what is the meaning of this?
(pout significantly changes depending on the running processes)

2)
sometimes react output
of vmstat is given in K like 44K
sometimes it is given without any unit like 6263.
this happens on the same system in 1 minute interval.
what is the relation between these two values?

r w u act free wire fault cow zero react pin pout in
1K 229 867K 960K 203K 364K 20K 187K 0 44K 0 5K 239K
1K 229 904K 922K 203K 62881 2819 26K 0 6263 0 3K 119K

Page out is when the system dumps a page to disk that hasn't been accessed in the timeframe set up - meaning no one attempted to access that page (the data that was taken from disk and put into memory) AND someone has requested some other data to be read and the system needed to dump some of the data it had in memory for the new data being requested.

Page in is when someone DOES request the data that was accessed a while ago but had been paged out (the data was sent to disk). The system gets the data that was paged out (as long as it hasn't changed) and brings it back into memory. Having pagein at zero would be expected on a server.