Update README.md

README.md

@@ -56,6 +56,7 @@ vim .env # edit your config
 + `MAX_ACCOUNT_BALANCE`: (default: 0 = no limit) Set maximum balance (in satoshi) for each account
 + `MAX_SEND_VOLUME`: (default: 0 = no limit) Set maximum volume (in satoshi) for sending for each account
 + `MAX_RECEIVE_VOLUME`: (default: 0 = no limit) Set maximum volume (in satoshi) for receiving for each account
++ `MAX_VOLUME_PERIOD`: (default: 2592000 = 1 month) Rolling period over which the volume should be calculated in seconds 
 + `SERVICE_FEE`: (default: 0 = no service fee) Set the service fee for each outgoing transaction in 1/1000 (e.g. 1 means a fee of 1sat for 1000sats - rounded up to the next bigger integer)
 + `NO_SERVICE_FEE_UP_TO_AMOUNT` (default: 0 = no free transactions) the amount in sats up to which no service fee should be charged