Yes. To our knowledge, those coins were lost early in the project by an early adopter due to a hard drive failure. When you 'lose' coins, you only lose the private key; those coins are still valid. For that reason, we have not excluded them from the total in circulation. However, for all intensive purposes, those coins should be considered out of circulation.
You can try to calculate the estimated value of.
Addresses and coins on them can be found here:
https://chainz.cryptoid.info/explorer/index.stats.dws?n=500&coin=rads500 addresses is 3059286 coins (99,89% of all coins).
Take the date of 1 January 2016. And look at what address did not change after this date.
Then calculate the amount of coins: total 239556 coins (7,82% of all coins).
A year has passed, so I think that these coins will never be used.