I currently have 291 decayed coins.
A basic calcualtion assuming a linear rate will would indicate 4x return (3x net) over about 8 years.

For those interested in the return from burning coins, I have updated the spreadsheet I started:
https://drive.google.com/open?id=1b04jiUde-wWvyk7yXzWibVeYc03yz0MB

Hi everyone,

I recently burned 10000 slimcoin, and have been keeping track of the results on a spreadsheet, with a graph of accumulated slimcoin minted by burn:
https://drive.google.com/file/d/1b04jiUde-wWvyk7yXzWibVeYc03yz0MB/view?usp=sharing

So far, assuming a linear income (I know it is not, but don't have enough data to know how it is shaping), it looks like being 2 years before I start getting any actual return from my investment.  That seems a bit too long for encouraging people to burn.

Thanks iguanodon1 and gjhiggins, staking is working properly now. 
I had tried gjhiggins previous sugesstion and I thought I had put a repy on this forum but something didn't work at the time

Hi Everyone,

A couple of months ago I bought some Slim, and today, I started staking them.  However, there seems to be two problems.
One is that I am getting huge  amounts of minted coins, generally around 16670 or 7490 per block.  Is this a bug, or is it because I bought coins that had not been staked for ages?
The second issue is that they all, so far, have become orphaned. Sometimes I will get 3 confirmations on one of them before it becomes unconfirmed.

Some more information:
I have about 40000 Slim, and am staking with 0 reserve balance.
I am running from the latest source from github on Ubuntu 17.10.

Any idea what is going here?