Shakespeare produced roughly one-tenth of all the most quotable utterances written or spoken in English since its inception

From Shakespeare The World as Stage by Bill Bryson.  Chapter 5 page 114.

His real gift was as a phrasemaker. “Shakespeare’s language,” says Stanley Wells, “has a quality, difficult to define, of memorability that has caused many phrases to enter the common language.” Among them: one fell swoop, vanish into thin air, bag and baggage, play fast and loose, go down the primrose path, be in a pickle, budge an inch, the milk of human kindness, more sinned against than sinning, remembrance of things past, beggar all description, cold comfort, to thine own self be true, more in sorrow than in anger, the wish is father to the thought, salad days, flesh and blood, foul play, tower of strength, be cruel to be kind, blinking idiot, with bated breath, tower of strength, pomp and circumstance, foregone conclusion—and many others so repetitiously irresistible that we have debased them into clichés. He was so prolific that he could (in Hamlet) put two in a single sentence: “Though I am native here and to the manner born, it is a custom more honoured in the breach than the observance.”

If we take the Oxford Dictionary of Quotations as our guide, then Shakespeare produced roughly one-tenth of all the most quotable utterances written or spoken in English since its inception—a clearly remarkable proportion.