The Lockheed Martin and Raytheon “Javelin Joint Venture (JJV)” announced the contract on Aug. 28 to produce the man-portable, anti-armor weapons (ATGW), including 4,000 missiles for Ukraine.
I've heard a Javelin missile is near 100% efficient if it can get a good lock. Wikipedia says "The Pentagon claimed that of the first 112 Javelins fired by the Ukrainians since the start of the war, 100 missiles had hit their target"
Last I heard Ukraine had gotten through an estimated 2/3 of Russias entire tank stock, including tanks that could realistically be repaired. Doesn't account for potential purchases or getting really desperate and sending partially non-functional vehicles into combat.
you can use the javelin on anything, it will lock onto a hot exhaust. one was used to take out a low-flying helicopter in occupied Ukraine, they were used regularly to take out vehicle-borne IEDs in Iraq, and those are just pickup trucks with armor welded on. I've been told it won't quite lock onto a person, but in direct fire mode you can use it against infantry