df -H can't count

Hi,

Just noticed this in my df output.

[root@newknight root]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/hda5             2.0G  134M  1.7G   7% /
/dev/hda1              30M   11M   18M  35% /boot
none                   61M     0   61M   0% /dev/shm
/dev/hda7              28G  1.7G   25G   7% /spare
/dev/hda2             3.9G  1.9G  1.8G  50% /usr
/dev/hda3             3.0G  112M  2.7G   4% /var
[root@newknight root]# df   
Filesystem           1k-blocks      Used Available Use% Mounted on
/dev/hda5              2063504    136376   1822308   7% /
/dev/hda1                31079     10312     19163  35% /boot
none                     62816         0     62816   0% /dev/shm
/dev/hda7             29711956   1692496  26510156   7% /spare
/dev/hda2              4127108   1936064   1981396  50% /usr
/dev/hda3              3122988    114168   2850180   4% /var

These are chronologically seperated by about 4 seconds, its a new install and I'm the only user logged on.
[RedHat 7.3, fileutils-4.1-10 in case it matters]



According to df 
1936064 = 1.9Gb
1981396 = 1.8Gb

[root@newknight root]# bc
bc 1.06
Copyright 1991-1994, 1997, 1998, 2000 Free Software Foundation, Inc.
This is free software with ABSOLUTELY NO WARRANTY.
For details type `warranty'. 
1936064-1981396
-45332

So 1.9Gb - 1.8Gb = -45332

Help is it me or is this wrong ?

Regards
Gav


-- 
Gavin Jones
Net-Work Internet Ltd
T 01824 708780
F 01824 708781
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