How to calculate steady/incremental growth?
What stops you looking at lags?
df = data.frame(c(1,2,3,4,4,3,4,5,6,7))
colnames(df)&lt;-c(&quot;price&quot;)
df$delta=lag(df$price, 1)
df$inc = df$price-df$delta
df

Would yield:
   price delta inc
1      1    NA  NA
2      2     1   1
3      3     2   1
4      4     3   1
5      4     4   0
6      3     4  -1
7      4     3   1
8      5     4   1
9      6     5   1
10     7     6   1

The condition here would be that each value of inc (except the first one) must be $&gt;0$.