conc	code
1	28.2	1
2	33.2	1
3	36.4	1
4	34.6	1
5	29.1	1
6	31	1
7	39.6	2
8	40.8	2
9	37.9	2
10	37.1	2
11	43.6	2
12	42.4	2
13	46.3	3
14	42.1	3
15	42.5	3
16	48.8	3
17	43.7	3
18	40.1	3
19	41	4
20	44.1	4
21	46.4	4
22	40.2	4
23	38.6	4
24	36.3	4
25	56.3	5
26	54.1	5
27	59.4	5
28	62.7	5
29	60	5
30	57.3	5