average s x y average x s y average x s s s y s average s x y average 0 0 0 average 0 s 0 0 average 0 s s 0 s 0 2.2 average s x y average x s y average x s s s y average s x y true average x s s s y average s x y average s x y average x s y true s 1 1 1 average 2 0 0 0 0 average 2 1 2 0 average s x y average x s y average s x y average x s y true s 1 1 1 average 2 0 0 0 0 average 2 1 0 NaTT certifiable-1.6