use CGI qw/:cgi/;

##</code><code>##

print STDOUT "The tax year is @{[ param('TAX_YEAR') ]}";

##</code><code>##

print STDOUT "The tax year is ", param('TAX_YEAR');

##</code><code>##

use constant DOWNPAYMENT => 'DOWNPAYMENT';

##</code><code>##

print STDOUT "Downpayment is: ", param(DOWNPAYMENT);

##</code><code>##

# Gives an error
print STDOUT "Downpayment is: ", param(DOWNPAMENT);