.074 is roughly half of .15.

This is the amount that was paid in Steem Dollars, which are supposed to be equal in value to U.S. Dollars.

The other half of your payment was made in Steem Power. Where 1 Steem Dollar equals 1 U.S. Dollar, 1 Steem Power DOES NOT equal 1 U.S. Dollar.

You were paid $.074 worth of Steem Dollars (which came out as .074 SD) and $.074 worth of Steem Power (which bought you .021 SP).

I hope this helps.