THERE ARE two ways to view yesterday’s cabinet reshuffle by Rishi Sunak, which saw the disposal of Suella Braverman as home secretary and the return of David Cameron to the front line of British politics. It’s either the death rattle of a tired government or a masterstroke of lateral thinking.

Whatever the interpretation, big cabinet reshuffles—which we define as more than four cabinet ministers moving in a single day, or any one of the chancellor, home secretary or foreign secretary switching posts—used to be relatively rare occasions. In the 30 years before the Brexit referendum vote in 2016 they happened about once every two years. But in the tumult that has followed reshuffles have occurred every six months on average. Constant churn at the top of government is bad for continuity of policy. Do reshuffles have any impact on voters?

To find out, The Economist looked at reshuffles of yesteryear, using a database of government ministries maintained by the Institute for Government, a think-tank. We matched data going back to Margaret Thatcher’s government (which began in 1979) with polling figures, to see how a party’s standing changed in the eight weeks before and after each major reshuffle.

All in all, we find that reshuffles have a negligible effect on voters’ intentions. Some prime ministers appear to have been better at executing cabinet changes, or at least timing them, than others (see chart). But, overall, the share of the electorate intending to vote for the governing party declined by an average of 0.3 percentage points in the eight weeks after a major reshuffle, compared with a 0.1 percentage-point decline before the cabinet change was announced. This should come as little surprise: changes to the cabinet are often not performed from a position of power.

That is certainly true of Mr Sunak’s shakeup. According to our poll tracker, the Conservative Party’s massive 21-percentage-point deficit to Labour has been widening of late. The reshuffle won lots of attention but it has also prompted a new round of Tory infighting. It is very unlikely to change the bigger picture. ■