Hi I want to be able to count strings of consecutive numbers in the one column.

eg:

Seagrass
Seagrass
Seagrass
Seagrass
NA
NA
NA
Seagrass
Seagrass
Seagrass
NA
...

So i want to count the number of times Seagrass occurs in the one string,
then count how many times it occurs int he next string. eg in the example
above: 4 & 3.

I am at a total loss

thanks