If you're into the whole stats thing, 45 of my short stories, 28 of my poems, and about 75 of my freelance essays and articles have been or will be published. However, through the mad power of reprint markets and the not-so-mad power of selling to magazines that paid on acceptance but went under before publication, I have 75 short story sales (if the IRS counts 'em, so will I).
If there's a take-home message in all that, it's this: if you have a story, and you sell it ... you can surely sell it again.
And: don't give up if at first a story doesn't sell. Persistence pays off. One of the members of my local writing group recently sold a story that had gotten 24 rejections. I have a story that was rejected 5 times over four years (slow response times!) before it sold to a semi-pro market ... and then in subsequent years I've sold it another 4 times, once for pro rates.