Thanks for the graphs.
I just calculated the "expectable" minimum (a sort of median between the minima of the last years) and subtracted it for each sea from the actual value (12 July before the Hudson millenium of today). Thus CAB should lose 0,9 mio. km², CAA 0,5 mio. km², Beaufort 0,3 mio. km², Grønland Sea 0,1 mio. km², Baffin 0,3 mio. km², ESS 0,6 mio. km², Chukchi 0,2 mio. km², Laptev 0,2 mio. km², Kara 0,25 mio. km² and Hudson 0,4 mio. km².
This sums up to 3,75 mio. km² which then (Extent on July 12 = 8,5 mio. km²) would result in a minimum of around 4,75 mio. km², a value quite comparable to 2017 and in an expectable range of many of us.