NEMA's T5 and T8 linear fluorescent lamp indexes surged upward 6.3% and 15.7%  on a year-over-year basis, respectively, during the first quarter of 2013. Moreover, the T8 index value of 120.2 was the second highest in the history of the series. Meanwhile, the index reading of 173.9 for T5 lamps was the highest since 2011. Not surprisingly, the index for T12 lamp shipments continued to diminish, posting a decrease of 38.9%, settling at a value of 36.5 for the quarter.

T8 lamps increased in market share by 2.2% reaching 75%. The increase came at the expense of T5 and T12 lamps. T5 lamps garnered a share of 10.1%, a decrease of 0.2%. Shipments of T12 lamps gave back the remaining 2%during the quarter, dipping to a share of 14.9%.