That is true... however:
In the 2 years before the last halving (2010-11-27 -- 2012-11-27) the price rose from ~0.28 to ~13 $/BTC (~45 times)
The price was practically flat around the halving (on 2012-11-28) and for the next 5 weeks.
In the 2 years after that halving (2012-11-29 and 2014-11-29) the price rose from ~13 to ~330 $/BTC (~25 times)
These numbers do not seem to indicate a significant correlation between the block reward and the price evolution.
Moreover, the rallies in 2013 have other explanations, not related to the reward: Bobby Lee took the command at BTC-China, OKCoin and Huobi opened in Mailand China, and bitcoin was "discovered" by some big investors like Fortress and marc Adreessen, and by the legion of Chinese amateur commodity traders.
By the way: the crash of Dec/2014 was clearly due to developments in China, so the preceding rally must have been born there, too.