2016 Postmortem

And your ignorance is showing...I can't argue against a person who shouts the same thing over and over insisting they are right when all evidence points to the contrary....I'll leave you with this hypothetical and extremely simplified version of the nonsense you're trying to pull(as this example shows the error upfront, and you're relying on no one digging into the actual numbers or fact checking):

I want to know how many of the entire 3 million people in Iowa support Hillary Clinton, so I poll a sample of 10000 Iowans. Of those 10000 I poll, 9000 of them declare their support for Hillary! So using the DanTex school of magical numbers I can boldly claim that 0.3% of Iowans support Hillary.

That is your argument in a nutshell...extrapolation takes the results of the subset and uses it to make inferences on the superset. You just take every number not included in your subset and claim it counts in your favor.

REAL MATH:
Securities and Investments: $12,774,649 (I'll give you this number even though it should include real estate as well)
Total INDIVIDUAL/PAC Contributions:
$376,309,659
- $13,453,821
- $20,903,972
------------------
$341,951,866

(your number inflates this by at 10% by including self financing by Hillary, as well as any loans taken out or interest earned while running the campaign...since we are specifically talking contributions and not sources of funding, these numbers do not belong in your calculation).

So before even reaching my main reason this number is BS, you're already wrong, and the percent would be 3.73%. No specialized knowledge needed, yet you still managed to fuck it up.

But that number is still entirely pulled out of ones ass, and is just as pointless as yours. The real issue is this: Of the 341 million dollars, only $138,954,124 of it have actually been designated with an industry(the donations over $200), leaving:

$341,951,866
-$138,954,124
------------------
$202,997,742

worth of contributions with no industry data. This results in two data sets that cannot be used together in the way you have done. You've taken all contributions with no industry data and dishonestly inferred that none of it came from the financial industry, with no data whatsover to back up:

($12,774,649 / $376,309,659 (false initial number)) * 100 = 3.39% WRONG!

In actuality, unless you want to end up with my Iowa scenario above, the only thing you can do is take the financial industry donations and compare them to the other donations that have industry designations as well, which gives you a closer picture:

($12,774,649 / $202,997,742 (donations which have industry data)) * 100 = 6.3%

Now you could take that number and try to make the assumption that it holds true for all her contributions since it is a large subset of the data, but I wouldn't go that far, since we're talking people in different income brackets many of which probably aren't associated with banks, so the only real conclusions that can be made from this data are:

1) Banksters donated 6.3% of all donations over $200 to her campaign.
2) The ABSOLUTE LOWEST amount the banks could have donated to her total campaign would be 3.73%, and that is only if every untracked donation was unassociated with a bank.
3) The ABSOLUTE HIGHEST amount the banks could have donated to her total campaign would be 63.1%, and this only if every untracted donation was associated with a bank

One final note, I mentioned that real estate should be included with banks, and they really should, especially since too big to fail and the mortgage crisis had to do with banks and sub-prime mortgages(under sectors in the link you provided they actually are listed together), so just to quickly show how drastic the numbers become with that added in, here you go:

Total Sector Donations: $173,573,828
Banking/Real Estate Donations: $34,996,285
Unknown Donatons: $168,378,083

($34,996,285 / $173,573,828 (donations which have sector data)) * 100 = 20.16%

So 20.16% of all donations over $200 comes from the banking/real estate sector.
The ABSOLUTE LOWEST amount the banking/real estate sector could have donated was 10.23%
The ABSOLUTE HIGHEST amount the banking/real estate sector could have donated was 59.37%

There you go, thoroughly and completely debunked. You just keep on dividing one number by another, maybe one day you can do math too. And I'd probably try to dabble in that special knowledge you don't think is required if I were you. Knowing is half the battle.