Pretty shit and all over the place.
It's sourced and dated estimates. Makes for a nice starting point for the minimums. After that you're left either getting into evaluating how plausible Russia and Ukraine's claims about their kill counts are, or just straight up pulling numbers out of thin air.
I'd imagine it's something like 10,000 KIA + WIA for Russia and 18,000 KIA + WIA for Ukraine, fairly close to a 2:1 but not all there given that there's a general parity between them in terms of numbers and equipment. If/when Russia starts sending in frontline units that'll more than likely change. I think Russia's underreported their losses overall, but I think their estimates are still more accurate than Ukraine's. Last I checked they were claiming something like a 10:1 ratio against Russian forces.
Last I checked was a bit over a week ago. Ukraine's claims were at a roughly 7:1 ratio, while Russia was the one claiming a 10:1 ratio. Looking back to what we were arguing at the time, Russia was claiming 14,000 Ukrainian soldiers killed and 16,000 wounded as of March 25th, while Ukraine as of April 15th was claiming 19,000 to 20,000 Russian soldiers killed(article linked just said casualties but was clearly using it to mean killed), and no estimate of how many they'd wounded.
So taking Russia's claims at face value, as of March 25th Russia was claiming 14,000 kills to 1,351 deaths, or a ratio of roughly 10.36:1 kills/deaths and 16,000 enemies wounded to 3,825 injured soldiers or a ratio of roughly 4.18:1 wounds inflicted/suffered. Taking Ukraine's claims at face value, as of April 15th they were claiming up to 20,000 kills to 3000 deaths, or a ratio of roughly 6.67:1 kills/deaths. While admitting to 10,000 wounded and making no estimate of how many Russians they'd wounded. So I'd take Ukraine's claims here as far more likely by virtue of them having the less absurd ratio claimed. Especially as their April 15th claim was no more than 5000 more than the upper end estimate from NATO on March 23rd three weeks before. Which would be consistent with Ukraine getting a lot of kills in poorly guarded supply lines to the north early on when Russia basically thought they could just walk in and take over, then having less success after Russia got smarter and eventually pulled back.
Now, taking both sides kill claims at face value we're at 20,000 Russian soldiers killed vs 14,000 Ukrainian soldiers killed, or a ratio of roughly 1.43:1 in Ukraine's favor. If you take into account the time difference between when each side made their claim, it probably gets even closer to even.