function calculate()
{
document.calculator.RuralImpressions.value = (document.calculator.RuralPeak.value*1860+document.calculator.RuralOffPeak.value*1380);
document.calculator.SuburbanImpressions.value = (document.calculator.SuburbanPeak.value*2880+document.calculator.SuburbanOffPeak.value*2100);
document.calculator.UrbanImpressions.value = (document.calculator.UrbanPeak.value*3840+document.calculator.UrbanOffPeak.value*3120);
document.calculator.SecondaryImpressions.value = (document.calculator.SecondaryPeak.value*5100+document.calculator.SecondaryOffPeak.value*4080);
document.calculator.MajorMarketImpressions.value = (document.calculator.MajorMarketPeak.value*23520+document.calculator.MajorMarketOffPeak.value*20400);
document.calculator.SecondaryMarketImpressions.value = (document.calculator.SecondaryMarketPeak.value*14700+document.calculator.SecondaryMarketOffPeak.value*12120);
document.calculator.MetroImpressions.value = (document.calculator.MetroPeak.value*3300+document.calculator.MetroOffPeak.value*2640);

document.calculator.TotalDailyImpressions.value = (parseInt(document.calculator.RuralImpressions.value)+
parseInt(document.calculator.SuburbanImpressions.value)+parseInt(document.calculator.UrbanImpressions.value)+
parseInt(document.calculator.SecondaryImpressions.value)+parseInt(document.calculator.MajorMarketImpressions.value)+
parseInt(document.calculator.SecondaryMarketImpressions.value)+parseInt(document.calculator.MetroImpressions.value));

document.calculator.MonthlyImpressions.value = (document.calculator.DaysPerMonth.value*document.calculator.TotalDailyImpressions.value);
}