calculate duration between two dates excluding weekends
NETWORKDAYS.INTL(D3,E3,0000000) calculates whole days between the two dates (no weekends, no holidays). NETWORKDAYS(D3,E3,0000000,$A$16:$A$24) calculates whole working days days between the two dates (Sat/Sun weekends, holidays as per your list in $A$16:$A$24). Difference in non-working days between the two dates.