The Bureau of Labour Statistics just published this fun graph which shows summer employment peaks in a handful private-sector industries, not seasonally adjusted, for January 2004 through Mary 2014.
Employment in these industries follow a regular, perennial pattern: there is maximum employment in the summer and minimum employment in the winter.
The industry with the largest per cent change is the recreational and vacation camps (green).
However, per cent change is not the whole story. The actual numerical difference of hired people is around 53,000.
In contrast, employment by golf courses and country clubs (navy) changes by an average amount of 206,000 people — even though the actual per cent change is lower.
The hotels and motels excluding casinos industry (dark red) has a difference of about 150,000 employed, despite the fact that the curve on the graph does not look as extreme.