
0.5% of total payment volume
From the total amount spend with the TenX cards, 0.5% is rewarded to the token holders. These token holders must have their tokens in an self controlled wallet, from which they own the private key.
For more information, check the
TenX official website

0.1% for cardholders
Cardholders get an extra 0.1% of their payments back from TenX.
For more information, check the
TenX official website

Total payment volume
The total payment volume was $20 million dollar in november 2017. This is where the calculator is based on.
For more information, check the
source on Twitter
TenX (PAY) token distribution overview
Payment volume, in millions of dollars
Buy, sell and trade TenX (PAY) tokens on Bittrex.
Bittrex is an exchange where you can buy TenX (PAY) tokens for bitcoins.

Store your tokens online at MyEtherWallet.com
MyEtherWallet.com is one of many options. Always be sure to check the link in your address bar if you visit your wallet.

Store your tokens offline. Potentially safer vs online.
Storing your tokens offline eliminates the risk of going to the wrong URI and providing your private key there. However, the safety of the machine where you store your wallet is of great importance. Maybe try a Ledger Nano S?