Per the Energy Policy Act of 2005, this began March 11, 2007, 3 weeks earlier than in 2006
[DOC] [TLE] The Effect of Early Daylight Saving Time on California Electricity ... [PAR] The Energy Policy Act of 2005 extended Daylight Saving Time (DST) by three 
weeks in the spring and one week in the fall, beginning on March 11 of this year, 
... Staff compared daily total electricity use in the early DST weeks of March 2007 
to ... Electricity use responds differently to weather in March than it does in winter.