Only Google has those numbers. They do share with certain groups (like if you're a huge spender in auto they'll show you how you stack up to the auto industry) but they won't just hand out the data to anyone.
I know that forex CPC's are $6 on average, CPM's are very varied but for larger sizes (so no buttons) its about $10-15.
Did Google share that with you? If not and you're arriving at an average based on your own account (and maybe a few others) that's not giving you any ttype of real average for an entire industry. That would pointless, you wouldn't learn anything of any value.
We would learn the CPC range of the industries represented here. I think that would be of value. At least an indication, and this is quite a large sample.
I don't think a few random people voting on a poll would be of any value. To get an average for a vertical you would need to poll the entire vertical - which only G' can do with any level of accuracy. This forum is busy but we probably represent 0.0000000000000000001% of AdWords advertisers. Anyone who wants can start a poll (I think there's been a few dozen over the years) but personally I just don't see the value.