y=[11.9	22.8	18.7	20.1	12.9	21.7	27.1	25.4	21.3	19.3 25.4	27.2	11.7	17.8	12.8	23.9	22.6	25.4	14.8	21.1];
 x=[1       1         1     1        1       1       1       1       1        1         1        1        1       1       1      1       1        1      1 1;
     19.5	24.7	30.7	29.8	19.1	25.6	31.4	27.9	22.1	25.5 31.1	30.4	18.7	19.7	14.6	29.5	27.7	30.2	22.7	25.2;
     43.1	49.8	51.9	54.3	42.2	53.9	58.6	52.1	49.9	53.5 56.6	56.7	46.5	44.2	42.7	54.4	55.3	58.6	48.2	51;
     29.1	28.2	37	31.1	30.9	23.7	27.6	30.6	23.2	24.8 30	28.3	23	28.6	21.3	30.1	25.6	24.6	27.1	27.5
     ];
 [b,bint,r,rint,stats]=regress(y',x')