The following table lists monthly stock prices in Canada as measured by the S&P/TSX Composite Index (this is CANSIM II series V122620) for 2011.

January .................................. 13551.99
February .................................. 14136.5
March ...................................... 14116.1
April ....................................... 13944.79
May ........................................13802.88
June ....................................... 13300.87
July ......................................... 12945.63
August ..................................... 12768.7
September ............................ 11623.84
October ................................. 12252.06
November ............................. 12204.11
December .............................. 11955.09

a. Which month would have been the worst month to buy the index?

b. What was the percentage decline in the index from January to December?