NEMA’s incandescent lamps shipment index for Q3 2011 decreased 1.2 percent from the previous quarter, but was up 21.5 percent compared to the same period last year. The year-over-year percentage (y/y) change is the largest swing, in either direction, since 2008. Compact fluorescent lamps (CFLs) shipments registered a slight gain of 0.9 percent over Q2 2011. Yet, the index declined for the fourth consecutive y/y comparison, sinking 15.4 percent.
 
Shares of the two lamp types were essentially unchanged compared to the previous quarter. Incandescent lamps decreased 0.4 percentage points to 79.4 percent. Meanwhile, CFLs increased marginally to reach 20.6 percent of the combined incandescent–CFL lamp market.