What length should a billiard table lamp be?

The typical bar table in the US uses a 4 foot fluorescent light with 2 40 watt lamps. The 9 foot tables most often have 3 incandescent lamps, each from 60 to 100 watts, inline above the table, although 8 foot fluorescent lamps are also used, with 2 to 4 40 watt lamps. For professional televised events, floodlights are typically used.