Oh dear, they seem to have suffered badly!

I was going to suggest it’s due to so much wet weather, but don’t know if it’s particularly wet where you are, plus I’ve only had big losses in very dry conditions.  No problems with dry conditions here in Berkshire this winter, and our daffodils are looking good, with lots of buds, some with a touch of yellow. 

If you’re missing a lot of plants I think it’s unlikely that so many have all gone ‘blind’ in the same year, unless they are very overcrowded, but you could try feeding those that are left next winter as the growing points start to show. For those that do flower, strengthen them with a liquid feed such a tomato food every couple of weeks until the leaves turn yellow. Excellent for daffodils in containers too.

Any that aren't flowering but are overcrowded would benefit from lifting when the foliage dies back in the spring/summer, then improve the soil with organic matter and some general purpose fertiliser and then re-plant the bulbs, leaving a 2-3 cm gap between each one to create good size clumps.

Sorry if you know/already do all that. Good luck for your daffodils next year.