XA_1:=90;
XA_2:=XA_1+(100-XA_1)/2;
XA_3:=(100-XA_1)/2;
XA_4:=COST(XA_2);
XA_5:=COST(XA_3);
Scr1:(XA_4-XA_5)/(XA_4+XA_5/2)*100;
XA_1:=90;
XA_2:=XA_1+(100-XA_1)/2;
XA_3:=(100-XA_1)/2;
XA_4:=COST(XA_2);
XA_5:=COST(XA_3);
Scr1:(XA_4-XA_5)/(XA_4+XA_5/2)*100;