Comments by Furqan Akhtar (Top 4 by date)

for ($y = $addPreviousEntryDate; $y <= $nowDate->format('Y'); $y++) {
// Find Years..
$year_arr = [$y];
$fn_month = 07;

foreach ($year_arr as $year) {
// Get start date and end date of each financial year..
$end_date = new \DateTime($year . '-' . $fn_month . '-01');
//last amount with interest
$sum = $amountwithinterest;
$start_date = clone $end_date;
$start_date->modify('+1 year');
$end_date->modify('+2year , -1day');
$year = array();
$year[] = array('start_date' => $start_date->format('d-m-Y'), 'end_date' => $end_date->format('d-m-Y'));
}

foreach($year as $example){
// Get no of days different each year.
echo "".$example['start_date']." - ".$example['end_date'].'-';

$difference = strtotime($example['end_date'])-strtotime($example['start_date']);
$diffinDaysYears = floor($difference/(60*60*24));

//Get Interest rate of each year..
$interest = $sum*($lastInterest->interest_rate**($diffinDaysYears/365));
echo $interest;
}
}