“The first lesson that you must learn is that, when I call for statistics about the rate of infant mortality, what I want is proof that fewer babies died when I was Prime Minister than when anyone else was Prime Minister. That is a political statistic.”

When Churchill was in opposition after 1945, he led the Conservative Party in a debate about the Health Service. As he listened to Aneurin Bevan’s opening speech, he called for some statistics about infant mortality … [which were] supplied, copiously and accurately, by Iain Macleod, then working in the back rooms of the Conservative Research Department. But, in his speech, Churchill made only one bold and sweeping use … [of Macleod’s detailed research]. Encountering MacLeod afterward, Churchill made the above statement. As cited in The Life of Politics (1968), Henry Fairlie, Methuen, pp. 203-204.
Post-war years (1945–1955)
Context: I gather, young man, that you wish to be a Member of Parliament. The first lesson that you must learn is that, when I call for statistics about the rate of infant mortality, what I want is proof that fewer babies died when I was Prime Minister than when anyone else was Prime Minister. That is a political statistic.