A method and apparatus for controlling a dose of extreme ultraviolet (EUV) radiation generated by a laser produced plasma (LPP) EUV light source. In one embodiment, a running total of the EUV energy generated over a predetermined number of laser pulses is measured; once that number of pulses is exceeded, the energy from the pulse immediately preceding the most recent predetermined number of pulses is dropped from the running total, so that the running total is from the most recent predetermined number of pulses. If the running total of the EUV energy exceeds a target dose, the next pulse is caused to not hit a droplet. This avoids the unwanted side effects of various prior art solutions, such as needing to miss many droplets in a row, or requiring the laser pulses to be shortened or reduced in power as in other prior art solutions.