Wounded Ukrainian troops receive treatment in Latvia.

Around 9,000 Ukrainian troops have died since Russia widened its war in Ukraine in late February, Ukrainian commander in chief Gen. Valerii Zaluzhnyi said Monday.

It’s the first official casualty figure to come out of Kyiv in six months of fighting—and it helps to put into perspective Russia’s own, much heavier losses.

But the upshot, for both armies fighting in Ukraine, is that this war is a bloody one. And the death toll is a major factor in what each army can achieve moving forward.

Zaluzhnyi mentioned the casualty count in a speech at a veterans’ event, when he referred to a Ukrainian child who would need care because “their father went to the front line and, perhaps, is one of those almost 9,000 heroes who died.”

If 9,000 Ukrainian soldiers, sailors, marines and airmen have died, it’s likely 20,000 or 30,000 have been wounded, as modern warfare tends to produce several wounded for each soldier killed in action.

An overall Ukrainian casualty count—dead and wounded—of, say, 39,000 is roughly half the tally of Russian dead and wounded. On Aug. 8, U.S. Undersecretary of Defense for Policy Colin Kahl told reporters between 70,000 and 80,000 Russians had been injured or killed in Ukraine since February.

The Kremlin does not release official casualty figures, and Kahl acknowledged that the number is an estimate. But it’s consistent with other estimates. Way back in mid-May, the U.K. Defense Ministry estimated the Kremlin had buried 15,000 troops as a result of the fighting in Ukraine. Add the likely wounded and you have as many as 60,000 casualties three months ago.

If 60,000 killed and wounded seems like a lot for an invasion force initially numbering just 125,000—well, that’s because it is.

But it’s also feasible, considering that the one entity on the Russian side that reports its casualties—the separatist Donetsk People’s Republic—in late May reported losing 2,057 soldiers killed in action and 8,526 wounded in action since February. That’s 10,583 casualties out of a pre-war force of just 20,000 troops.

Notably, some of the most intensive fighting happened after May, as the Russian army retreated from its disastrous attempt to capture Kyiv and instead concentrated its forces in eastern Ukraine’s Donbas region for much less ambitious operations.

Fifty battalions with tens of thousands of troops and hundreds of artillery pieces targeted Ukrainian settlements just miles from territory Russia has held since first invading Ukraine eight years ago.

The battles for cities and towns such as Severodonetsk, Lysychansk and Pisky were brutal, slogging affairs. Russian artillery barrages were relentless, but so was the Ukrainian gunfire when the Russian infantry attempted direct assaults on dug-in positions. Officials in Kyiv in June claimed their forces were losing up to 200 troops a day.

Two hundred WIA and KIA a day might have been the peak casualty rate for the Ukrainians, but that figure is consistent with the likely six-month toll of dead and wounded. It’s possible Ukrainian troops have been dying and getting hurt at a similar rate for the entire six months of the wider war.

The Russian army’s steep losses have weighed on its ability to conduct sustained offensive operations across a wide front. Every day the war grinds on, the Kremlin’s goals shrink.

Where once the Russians aimed to seize Kyiv and every other city east of the Dnipro River including Kharkiv while also cutting off Ukraine from the Black Sea, today Kyiv is safe, Kharkiv is safe and the Black Sea coast around Odesa remains under Ukrainian control. Today the Russians celebrate the capture of a few tiny, lifeless towns in Donbas.

But Ukraine’s losses also weigh on its potential for action. Kyiv’s pre-war military establishment included just 311,000 active and paramilitary troops. It’s possible one out of 10 have died or wound up in a hospital bed.

The proportion gets worse when you consider that most of the people in any modern army perform support functions. Just a fifth or so are “trigger-pullers” who do most of the fighting … and most of the dying. It’s possible a third of all Ukrainian infantry, tankers, artillery gunners and combat pilots have been hurt or killed since February.

No army can absorb such heavy losses without losing some capacity for offensive operations. That might explain why the counteroffensive that Ukrainian battalions launched toward Russian-occupied Kherson in southern Ukraine in May so far has succeeded in achieving only the most modest of goals: securing a lodgment across the Inhulets River.

So many people have died in Ukraine that, it seems, both armies are close to exhaustion.