If you're saying your prints don't come out looking like how they look on your monitor, not that they have deteriorated over time, we will need to know about how you're setting up to print. Is your monitor calibrated? Are you using Photoshop Elements to manage the color, or allowing the Printer to manage color settings? Are you making sure that if you've chosen Photoshop, you're turning off printer management in your printer's settings?
Printing is a very complex issue, so the more we know, including the OS you're using, the more likely someone here will be able to help. I don't use Elements (I use Photoshop), so if your printer dialog is different from Photoshop's, someone else will be able to help you with it. There are several Elements experts here.
Thank you for your response.
Yesterday, a friend came round and recalibrated the screen and checked the settings in the Epson printer software.
Prints seemed much better; the dull muddy colours were transformed back to their previous vibrant state.
Before the recent Windows 10 update all seemed to be fine but whether that is the source of the trouble I cannot say.
I will do some test printing today. If the trouble persists, May I come back to you?