Table 5. Chemically destroyed depth d₀ as a reliability process for parameters of log-normal distribution (μ, σ) with time influence.

Time [years]	μ [mm]	σ [mm]
15	-3.839	0.230
20	-3.640	0.236
25	-3.493	0.237
30	-3.379	0.243
35	-3.285	0.246
40	-3.202	0.248
45	-3.133	0.254
50	-3.066	0.254