raglan sleeve problem

The pattern I am using has a sleeve far to long so I have had to stop knitting it before i have fully cast on all the stitches. This means that I have fewer stitches to cast off to get to the full length of the raglan edge.
i.e. the pattern says I should carry on casting on until I have 64 sts. and then cast off 4 sts at each end of the next 2 rows and then carry on knitting casting off at each end of 1st and every following alternate row until there are 14 sts. left. however I only have 60 sts at the start so how many row do i need to knit until I get down to 14 sts,and have the right length of raglan.
sorry this is so complicated and hope someone can help.

Janet

What is the name of your pattern?

For the number of rows, if you start with 60sts minus the 4x2 sts that 52sts. It’ll take 38 rows to get to 14sts (52-14). You can use the row gauge to figure out how long that is.
The right length depends on the length that you would like.

I thought there would be a way to work it out. Thanks very much for your trouble.

The pattern is a Sirdar Chunky 8940.

Very nice!