According to some approved and credible sources, Russia is losing 1,500 soldiers a day and has been since October and have losses of 700,000 men
https://au.news.yahoo.com/russia-paying-extraordinary-price-ukraine-062643220.html
Considering this has been very much an artillery war and not hand to hand combat and that Russia is firing at least 5 times more artillery, one wonders what the losses on the other side is. I find Zelensky’s figure of 30,000 a bit questionable.