It changes with every block. The POS block reward is based on the last 3 digits of the block number. Example, the block reward for block 32266 would be 2.66

The POW block reward is based on the POS reward with a multiplier of between 0.1 to 1  (POS reward * multiplier = POW reward). This multiplier is based on a 10000 block cycle. Currently the multiplier is 0.2 (2.66 * 0.2 = 0.532 Swing)

http://i.imgur.com/hDPwemw.png