“not seen in several decades”
Guess it may be several decades before it’s seen again.
A figure of 870 millibar (25.69 in) was recorded on 12 Oct 1979 by the US Air Weather Service 483 km (300 miles) west of Guam in the Pacific Ocean in the eye of Super Typhoon Tip which involved wind speeds of 165 kts (305 km/h; 190 mph). Barometric pressure is the physical pressure exerted by all of the air above you.
Looks like 940 is a very low pressure. I am not sure if it is lower on average, near the tropics or near the poles.