As a result, the ratio of the number of payments made by mail to the number of bills received in the mail has dropped from 62.
The ratio has been cut in half, from 62 down to 31. 
mnli hypothesis: The ratio has been cut in half, from 62 down to 31.  premise: As a result, the ratio of the number of payments made by mail to the number of bills received in the mail has dropped from 62.