$w = 16;
$p = $this->data['ecdc']['DoseAdditional2']/100;
$v='';
for($i=1; $i< $w-1;){
    $v.=($i++==$w/2-1) ? '' : (($i<$w*$p)?'█':'░');
}
$DoseAdditional2 = $v;
...
....
2η Αναμνηστική:
{$DoseAdditional2}
{$this->data['ecdc']['DoseAdditional2']}%