strings.Split adds additional newline

After reading file using ioutil.ReadFile I try to split my "string" of bytes using strings.Split and separator "\n", but I receive an extra newline (the length of slice is increased by + 1).

Why is this not as expected?

// numbers.txt
1
2
3
4
5

func main() {
	data, _ := ioutil.ReadFile("numbers.txt")
	input := strings.Split(string(data), "\n")
    fmt.Println("Len: ", len(input))
	for i, v := range input {
		fmt.Println(i, v)
	}
}
// Output
Len: 6
0 1
1 2
2 3
3 4
4 5
5

Expected:

Len: 5
0 1
1 2
2 3
3 4
4 5

Could be duplicate of Read text file into string array (and write)
See comment

> Note strings.Split will append one extra line (an empty string) when
> parsing regular POSIX text files example – bain Dec 1 '14 at 20:33

strings.Split doesn't append an extra line - otherwise it would be specified in the documentation to it.
If you view your file as following:

1\n
2\n
3\n
4\n
5\n

You will notice, that there must be 6 entries if you split the string by \n.

1\n2\n3\n4\n5\n<last empty item is here>