带数字数组的PHP for循环可以以NULL开头，也有0吗？

I am working with some legacy PHP code so re-writing this isn't an option at this point but I have a dropdown for number of years and months of employment and currently they go from 0 - 11, 0 - 65. Can a PHP loop array numbers starting at NULL, which adds -Select- as the default forcing user to make a selection, but also have 0 as the starting number?

I've tried:

for ($i = NULL; $i <= 11; $i++) {
echo $i;
}

But 0 is no loner an option

This is what I have currently:

for ($i = 0; $i <= 11; $i++) {
echo $i;
}

I need it to display as: -Select- 0 1 2 3 4 etc

Echo the text before echoing the numbers using a loop.

<?php
echo '-Select-';
for($i = 0; $i <= 11; ++$i) {
    echo $i;
}

NULL++ would not increase the value of NULL, which is essentially nothing. Why not start at -1, and if ($i == -1) then echo select?

It would look like this:

for ($i = -1; $i <= 11; $i++) {
   if ($i == -1) {
       echo '-Select-';
   } else {
       echo $i;
   }
}