When to stop worker production

A long game, with up to 4 expansions, same goes for the opponant. Throughout a game, its vital to keep up your worker production to have the strong economy for the higher tier fights. You find yourselfe at 200/200, with a strong economy.

My questions is,

• At what point in the game should I stop my worker production?
• What is the optimal number of workers in late mid-game and late-game?

(if I keep producing workers, the workers will have an overweight compared to regular units, as the units die in combat)

EDIT: The obtimal number of workers are 24 workers + 6 on gas, or 3 workers per batch. The batches are cleared throughout the game length, and at some point in the game, the balance between workers and units could impact the outcome of the game. Thats the point of the questions.

The (maximum) optimal number is 3 workers per patch/vespene gas. The total number of workers for a single "base" is 16-24 workers. More than 24 is a waste of supply/workers. Because you'll have many workers waiting anyway, i.e. no mining going on.

On 20-24, you'll still have someone waiting but less. I think here you shouldn't focus on a hard number but decide on each case an optimal number (based on the number of patches available) of workers you should produce. Between 16-20 seems like a reasonable count, though.

Considering the 200 cap, I wouldn't go over 80/90 workers in total, i.e. consider that the real maximum. If less is possible, perfect. More workers don't mean more income. Or rather, considering the same amount of bases, more workers mean more income up to a certain point. After that point, you're not gaining more.

Think about the Vespene gas: 3 workers will be the most efficient number because if you add another or 2 workers, they'll still have to wait anyway before gathering it. The amount of Vespene coming to your CC/Hatchery/Nexus will be the same, at the same rate.

For minerals, 2 workers per patch is a lot more efficient than 1 worker per patch, but this efficiency decreases if you go from 2 to 3. There is still an improvement (even if minor compared to the first). 4 workers per patch is a waste of workers and they should be on another base.

I think that the production should start to decrease around your fourth base, as you should be between 64-80 by then. Keep producing until you have saturation on all your bases. If you see they're getting there, slow down the production, otherwise keep going on. However, the workers from the first bases will be transferred so there might be no need to create new ones. If you get attacked and your workers killed, recreate them, of course. Again, no hard numbers, it's all about keeping that count to have a decent/optimal income.

IMO, it depends what race you're playing as, and the map you're playing on. At some point in a late macro game, it's better to kill your own workers and produce a bigger army, but it depends on many factors. Here are some general suggestions:

Zerg: After you've secured your 3rd, stop major worker production. As you take your 4th base, you should consider cutting worker production entirely.

As you take your 5th or 6th base, consider "killing" some of your workers by making lots of static defenses at your bases, or offensively.

Terran: After you've secured your 3rd, stop major worker production. As you take your 4th base, cut worker production entirely. As long as you have several Orbitals and decent macro, you can spam MULE's and keep up just fine.

As you take your 5th or 6th base, consider killing some of your own workers (or sending them to the enemy base).

Protoss: After you've secured your 3rd, stop major worker production. As you take your 4th base, consider cutting worker production.

Protoss don't have the luxury of spamming MULE's or popping out a ton of workers at once if needed, so I would be more conservative with your workers. Consider killing off some of your own workers after you take your 6th base.

Conclusion: Again, all of this advice depends on the map. If it's a HUGE map where taking 6/7/8 bases is reasonable for late-game macro, then you'll kill your workers off later than if it were a tiny map where the game is over before getting a 4th base.

And of course, you'll have to use your own judgement. Depending on how the game is going, and what sort of unit composition you have, you may want to never kill your own workers. For example, if you have a mineral heavy Zerg army that is very inefficient, but you plan on hurling army after army at your enemy and rebuilding new armies quickly to continually chip away at the enemy, then you'll want to keep your workers and income going.

On the flip side, if you have a very expensive and highly efficient Protoss/Terran army, you'll likely want to kill some workers to make your army bigger and more efficient.