not exacly... you have to count how many rounds is bellow 50 lets say
morale = 50 - stay for sure - 1
morale = 43 - stay with 86% -0,86
morale = 36 - stay with 72% -0,72
morale = 29 - stay with 58% -0,58
morale = 24 - stay with 44% -0,44
morale = 16 - stay with 30% -0,30
now lets play with numbers
0,86*0,72*0,58*0,44*0,30 =~0,047 it means he was veeeery lucky because probabilty to stay in battle in this sequence was 4,7%
but of course. If you look at single event it is 30%