# Subtracting Dates

**URL:** <https://forum.kirupa.com/t/subtracting-dates/297123>\
**Category:** programming\
**Created:** [September 25, 2009, 10:56pm UTC](https://forum.kirupa.com/t/subtracting-dates/297123 "2009-09-25T22:56:13Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![GPP](https://avatars.discourse-cdn.com/v4/letter/g/848f3c/32.png) [@GPP](https://forum.kirupa.com/u/GPP)\
**Post date:** [September 25, 2009, 10:56pm UTC](https://forum.kirupa.com/t/subtracting-dates/297123/1 "2009-09-25T22:56:13Z")

</div>

I want to go 7 days back from a certain date but when I do so the days go into negative?

```php

<?php
$date = "09/01/09";
$date = strtotime( (string) $date );
$day = date('d', $date);
$month = date('F', $date);
$year = date('Y', $date);
for ($i = 1; $i <= 7; $i++) {
    echo "$month, $day, $year<br />";
    $day--;
}
?>

```

output

```auto

September, 01, 2009
September, 0, 2009
September, -1, 2009
September, -2, 2009
September, -3, 2009
September, -4, 2009
September, -5, 2009

```