---------all data----------------------- 
layer frac-ave   frac-sig   median-seeing
0001 1.80000E+01 2.30000E+01 5.70000E-01
0002 6.00000E+00 1.30000E+01 5.70000E-01
0003 1.20000E+01 1.50000E+01 5.70000E-01
0004 2.00000E+01 1.70000E+01 5.70000E-01
0005 2.50000E+01 2.10000E+01 5.70000E-01
0006 1.60000E+01 1.10000E+01 5.70000E-01
---------best 30 percentile--------------
layer frac-ave   frac-sig   median-seeing
0001 1.30000E+01 1.90000E+01 3.40000E-01
0002 2.00000E+00 8.00000E+00 3.40000E-01
0003 6.00000E+00 1.10000E+01 3.40000E-01
0004 1.60000E+01 1.50000E+01 3.40000E-01
0005 3.40000E+01 2.30000E+01 3.40000E-01
0006 2.60000E+01 1.20000E+01 3.40000E-01
---------worst 30 percentile------------ 
layer frac-ave   frac-sig   median-seeing
0001 2.60000E+01 2.70000E+01 9.20000E-01
0002 1.00000E+01 1.70000E+01 9.20000E-01
0003 1.90000E+01 1.70000E+01 9.20000E-01
0004 2.20000E+01 1.70000E+01 9.20000E-01
0005 1.30000E+01 1.20000E+01 9.20000E-01
0006 7.00000E+00 4.00000E+00 9.20000E-01
6 layers (centered at h=0.5-1-2-4-8-16km, thickness=3h/4)