No, I'm not going to give you any more lunch money

TRADE unions in Britain have lost much of the clout that they once wielded. Since 1979 membership has dropped in both the private and public sectors, while the number of days lost to strikes has plummeted (see brown line on chart). And under the Trade Union Bill, announced today by Sajid Javid, the business secretary, things are going to get even more difficult for them. The rules for striking will change. Under the current rules, all unions need to do to strike is get a majority of those voting. The new bill, though, would impose a minimum 50% turnout. In the case of “essential” public services they would need the support of 40% of eligible members.

Why, if so few days are lost to strikes, is the Conservative government so keen on a crackdown? Let's leave aside ideological or political motives (which are extremely difficult to divine) and focus on something crunchier. One explanation could be that striking workers are getting more visible. New figures released this morning show that the number of workers who went on a strike in a given year (as a proportion of the total population) has been on an unsteady increase since the 2000s (see blue line on chart).