How many knights sat at King Arthur's table?

There were originally about 150, but only 13 were the most important ones: King Arthur, Sir Lancelot, Sir Gawain, Sir Geraint, Sir Gareth, Sir Gaheris, Sir Bedivere, Sir Galahad, Sir Kay, Sir Bors de Ganis, Sir Lamorak, Sir Tristan and Sir Percivale.