24.2. Comparison of fair values and carrying amounts of financial instruments

As at 31 December 2020 and 2019, the carrying amount of the Group financial instruments excluding lease liabilities, except for telecommunications licence payables and a loan from related party based on fixed interest rate, approximated their fair value due to relatively short term maturity of those instruments, cash nature, variable interest rates or immaterial difference between the original effective interest rates and current market rates.

A comparison of carrying amounts and fair value of telecommunications licence payables and a loan from related party based on fixed interest rate, for which the estimated fair value differs from the book value due to significant change between the original effective interest rates and current market rates, is presented below:

(in PLN millions)

The fair value of financial instruments is calculated by discounting contractual future cash flows at the prevailing market interest rates for a given currency. Fair value amounts are translated to PLN at the National Bank of Poland period-end average exchange rate and adjusted by own credit risk. DVA estimates were not material compared to the total fair value of the related financial instruments.