I have made a simple Line Chart:

Which is showing 4 grid-lines at points 2, 9, 16, 23, which are generated by using the code:
hAxis: {
gridlines: {
count: 4
}
}
By using the above code, regardless of how much the data increase or decrease, it will always display 4 grid-lines.
Can I show grid-lines at a regular step interval. For instance, at 5, 10, 15, 20… and so on ?
In a continuous chart, no you can’t set the steps. (evil google)