I was always under the impression that the Total output drops was a counter that goes up until it resets (or maybe wraps around 4 billion).
However, this seems to indicate otherwise, or something is just messed up:
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 14456
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 3614
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 3614
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 3614
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 3614
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 3614
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 3614
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 3614
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 7228
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 7228
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 3614
Another Sample:
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 10908
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 10908
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 3636
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 3636
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 10908
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 10908
In both of these examples I am just running the command over and over again, ~ second or so between commands.