PHP Show options depending on the selected year - php

Question

I am trying to show options to the user according to the year he's selecting.
At the top of the file I have a function to retrieve the year, and send it back to the same page which is view2.php, but I'm sure I'm doing it wrong:
if(!empty($_POST['year'])){
$year = htmlentities($_POST['year']);
header('Location: view2.php');
//exit();
}
Later, I have a form submitting the year that looks like this
<form method="post" action="">
Select year:
<?php
$myOptions = array(
'All' => 'All',
'2013' => '2013',
'2014' => '2014',
'2015' => '2015',
'2016' => '2016',
'2017' => '2017',
'2018' => '2018',
'2019' => '2019',
'2020' => '2020'
);
?>
<select name="year">
<?php
foreach($myOptions as $key => $opt) {
$selected = null;
if(isset($_POST['View All']) && $key === $_POST['View All'])
$selected = ' selected';
echo '<option value="' . $key . '"' . $selected. '>' . $opt . '</option>';
}
?>
</select>
<input type="submit" name="submit" value="GO"/>
</form>
If I manually set the $year variable, my sql query works fine, so the function ($users->expensePerYear($username, $year, $i);) is okay. This is my function:
<?php
$i=0;
$year = 2013;
//if (isset($year)){
$users->expensePerYear($username, $year, $i);
$userQueryResult = $users->queryResult;
$count = $users->i;
$totalSpent = $users->totalSpent;
$remaining = $budget-$totalSpent;
The problem is that I'm trying to send the year variable to the same page and I'm doing it wrong. I want the user to specify the year in the select, send it to the same page and show stuff according to that variable.

Answer 1

Never mind me, I only had to comment the header() line and it works.
if (isset($_POST['submit2'])) {
$year = htmlentities($_POST['year']);
//header('Location: view2.php?$year=".$year."');
//echo $year;
}