Daylight saving time does not make a lot of sense for people who work 8-5, but in fields like agriculture where it is 7 or 8 a.m. to sunset, the time change gives more time on the tail end of the day- so instead of working 8-6 like now, it would be 8 to 7 (eventually even later).
The dates for Daylight saving time were changed a few years ago by President Bush to conserve energy by moving it back so there were more long days (so less light bulb usage).