You're the third person I know of who's had this problem. According to one of my independent paint dealers who sells a SW related product, they've undergone major formulation and base changes. Duplicating some older colors in paints and stains has been a problem.

The numbers don't mean much now because the system has changed.

Try and independent privately owned paint store. Paint a sample on something, let it dry overnite and ask them to match it. Most stores have a color computer that won't care about SW's old system or anyone else's.
By whose standard are you saying the match isn't good? Remember, the rooms may have faded somewhat and if you had a gallon of the very same paint, it also might not match.

Hi Fun-C!

OP-
Yep...most companies have different paints/colorants now. I've been a "Matchmaker" at a busy INDEPENDENT upscale retail store for a decade+ now.
* Like the television industry, "paint" has been undergoing a "sea-change" the last few years.
* Resin-changes/improvements have quickened.
* Colorants themselves are converting to low-voc "acrylic-blends".
* This alone requires many stores to change tinters, most of which run a ways into $five-figures.

Your remedies:
1) Pick a new similar color, and re-do affected walls.
2) Get it matched....but realize....even with fancy scanners, an exact match WON'T happen. It's "literally" technically impossible.
>>> After this long, I'm damn good at it....BUT.....

Faron

Retouching with stored paint is always iffy. Light, dirt and time will change the color on the wall and the paint is the can is undergoing its own changes.

To get the best match possible, ignore the formula and the name on the can and see what the paint really does:

1 - Stir the old can very thoroughly, being sure to scrape the bottom of the can of all settled pigment and stir it in.

2 - Pick an inconspicuous area of the painted wall and brush a bit of the well-stirred paint onto it and let it dry.

Check it to see if it still matches.

If it does, dip a paint stick into the paint, pull it out and let it dry. Have a paint store color match to the dried paint, and test by smearing a bit of the color-matched paint on some paper and holding it next to the paint stick - dry it first, of course.

If it doesn't, either find a spot where you can remove a bit of drywall with that color on it for matching or resign yourself to having obvious patches where you touch up the dings.

lazy - the problem is even when armed with everything possible, colorists are not able to duplicate some of the older colors. I understand the problem is happening with paints and stains.

Having the original formula, sample from the wall, a hand-painted sample -- all the standard things you reach for to match a color aren't working.

I wasn't around when the shift from lead-based paints happened but friends at the indy paint store equate what's happening now to then; there were colors that you could make because of the old ingredients and when the laws changed, it was no longer possible to make those colors.

Most colors it's possible to get spot-on or close enough but there are a few that no matter what, it just can not be made again because the ingredients (bases and colorants) to make it no longer exist.