[Kanegasi]

Here you go. I also future-proofed it by formatting higher numbers, if you ever run into that.

local function FormatValue(val)
    if val<1000 then return ("%.0f"):format(val)
    elseif val<1000000 then return ("%.1fk"):format(val/1000)
    elseif val<1000000000 then return ("%.1fm"):format(val/1000000)
    elseif val<1000000000000 then return ("%.1fb"):format(val/1000000000)
    else return ("%.1ft"):format(val/1000000000000) end
end
 
hooksecurefunc("CompactUnitFrame_UpdateStatusText",function(self)
    if self.optionTable.healthText=="health" and tonumber(self.statusText:GetText() or "") then
        local hp=UnitHealth(self.displayedUnit)
        local maxhp=UnitHealthMax(self.displayedUnit)
        self.statusText:SetText(format("%d%%     %s",hp*100/maxhp,FormatValue(hp)))
        self.statusText:SetTextColor(0.9,0.9,0.9,1)
        if not self.smallStatus then
            self.statusText:SetFont("Fonts\\ARIALN.TTF",14,"THINOUTLINE")
            self.smallStatus=false
        end
    end
end)