Here some explanation from the dev:
Stash was originally designed for a maximum supply of 1 Billion tokens. This will now be a maximum of 684 Million.
Originally 500M STP tokens were to be distributed in the token sale. When mainnet launched an additional 500M were for to be allocated to miners, masternodes and the budget system over time decreasing at a rate of approx. 7.1% per year (assuming 525960 blocks per year with 60 second block time).
Before the mainnet launch 280,555,476.76502248 (0x63ac5f393ca8e8 in hexadecimal) STP were burnt from the token sale vault:
https://etherscan.io/tx/0x9803cd4d6edeef556ca51a107fd23db948f47a6d77f53dbd68e143db95b1896a
An additional 36,281,574.83039780 (0x0ce3ca3df73c24 in hexadecimal) STP were subsequently burnt from the adviser and bounty pool:
https://etherscan.io/tx/0x8285f9ece7db723b45c58ed194c00bac63b1d3cb678c36e2e5217be63adb15fc
Together 316,837,051.59542028 STP burnt leaving a total supply of 183,162,927.10457 STP
The total STP Supply before mainnet launch can be confirmed here: https://etherscan.io/token/0xecd570bbf74761b960fa04cc10fe2c4e86ffda36
These balances were imported into the STASH mainnet with the public key mappings provided in the ERC-20 STP contract. For those that did not register a public key, we have deduced the STASH public key from the Ethereum public key (technically not the same as the Ethereum address which is a hash of the public key – this info was only available to addresses that had one or more previous transactions and have a tx signature).
It should be possible for the majority of those that did not map their mainnet STASH address to import tokens, however a tool must be written to convert an Ethereum private key to a STASH private key and due to time constraints and fairness to those that did register this has not been done but any community member should be able to implement.
At the time of launch 10 masternodes were run to initially bootstrap the network. These nodes were switched off around the end of April. The nodes were:
Xpv8zxHHH1tHU2HnbFbBjxv1uCrVK8oBtL
XdEwegeN9UMq3fBnoMuyD52XBoHme5wsG1
XgtR8Qg3ZDv4n2jF5zwejrYDzLGEtRdhrG
XnJDRLpvF9syYc99wWrby99n3JQ63ihLXu
XpHPe2YsjnuzF9ajicTqPvPvhkiYSvPpM6
XdqbcSWjWpsYvXVWHDxpayPvFxvptnr5kW
XwSGr2CPQ8DPyFWM6m12EXhFX3iaF1GjFW
XbVbYx3GAhFFbUqTC9eHKnRQBAHvtTC7V6
Xm4yXBbq7Mja42Mh19eXsztqZJQK9JVQbt
Xk9F4Yv8BSitutSswL2i1wk4DZ7PZM8vjh
The total payed out to these masternodes was 433,046.36011478 STPX
Also, while bootstrapping the mainnet 333048.30010185 tokens were mined to address Xj4YENArPqPMSiaziaasepj3jgqJY65cH3.
This gives a total of 766,094.66021663 STPX which are unspent and to be used as the community sees fit.