Calculate Insurance included in the fee for delivery

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There is no option to set correct price for shipping if you want to add Insurance for delivery.
In most shipping companies it is % of total price of ordered goods and minimum fee.

So if you buy Glasses for $500 and you want to included Insurance  in the fee for delivery you cannot. Shipping price $10.
% Insurance - 1%
minimum fee of insurance - $2

$500 * 1% = $5 > $2 -> $10 + $5 = $15 is total shipping price

If total order is for $100 we have
$100 * 1% = $1 < $2 -> $10 + $2 = $12 is total shipping price

Why there is no such option in shipping plugin? All shipping companies offer insurance as additional fee.