As Often As Not Meaning

(idiomatic) More or less half of the time; on many occasions but not always; frequently.

Example: 1841, Charles Dickens, The Old Curiosity Shop, ch. 7:
  "[T]hese old people—there's no trusting them, Fred. . . . [Y]ou can't calculate upon 'em, and even then they deceive you just as often as not."
1896, Robert Louis Stevenson, "The Persons of the Tale" in Fables:
  "I am a man that tries to do his duty, and makes a mess of it as often as not."
1910, H. G. Wells, The History of Mr. Polly, ch. 7:
  [I]f he discovered a sale where there were books he would as often as not waste half the next day in going again to acquire a job lot of them.
1918, Edgar Wallace, The Man Who Knew, ch. 7:
  The hall porter said that, as often as not, the flat was untenanted.
2012 Oct. 24, Eamon Javers, "Spies and Co.," New York Times (retrieved 29 Oct 2013):
  As often as not, the perpetrators have been other Americans — motivated not by patriotism for a foreign flag, but by simple profit.