function formatNumberDecimal(num)
local formatted = string.format("%.2f", num)
local intPart, decPart = formatted:match("^(%-?%d+)(%.%d+)$")
while true do
intPart, k = intPart:gsub("^(-?%d+)(%d%d%d)", "%1,%2")
if k == 0 then break end
end
return intPart ...