large smokestack reports TOTAL CONSUMPTION statistics incorrectly

Issue description

while trying to scrub the exhaust on my island I noticed this "Total Consumption" item in the statistics that doesn't make any sense. it shows up in increments of 0,50,100 (no other values). I finally tracked it down to the year that the statistic began, and it's when I was exporting a coal boiler's exhaust output to a large smokestack.

here's a picture of me adding the stack (the first value, 50), then I remove the stack and just use a normal stack for a few months, then add it back....

after that I see that it goes back to 50, but since it's not running all the time, I decide to vent the steam so that it's for sure running full speed.

now, even though I'm 100% sure that I'm outputting 60 exhaust (it's a coal boiler running full speed), it still says 50

now here's the weird thing: a truck comes over and dumps some animal feed into the boiler, and it spikes to 100 for a moment.

let it run for a few months at full speed coal only (no animal feed), and even still I get some spikes of 100 from time to time:

what I think is might be happening is that it's registering exhaust output in increments of 50, and since 60 is between 50 and 100, it says 50 usually,-- but then once every ~5 months or so it says 100. (not sure about this theory though -- doesn't seem so)

nevertheless, exhaust dumped in a large stack is definitely not consumed at all and should be under "DUMPED / DISPOSED" instead.

Reproduction steps

1. build large stack and export exhaust into it (see description above for exact steps I took)
2. look at the statistics
3. (save file is provided if you want to play with it)

Game version and build number

v0.6.4c (b341)

Operating system

Windows

Attachments

bug - big smoke stack exhaust.save

update: turns out there are other values -- a lot of other values --

but the weird thing is, if the "TOTAL CONSUMPTION" values are all coming from the big smokestack (I don't have any others), so I don't understand the numbers, because there are a lot of other exhaust outputters connected to it now, so the value should be much higher than 54 in the current month in this save just before I start the scrubbing planning and stuff -- (which btw it went terribly so I'm going to try again tomorrow, lol) upgrade kiln 1.2.save cheers!