log('Returns the number of days from the settlement date to the next coupon date.'); // Create new PhpSpreadsheet object $spreadsheet = new Spreadsheet(); $worksheet = $spreadsheet->getActiveSheet(); // Add some data $arguments = [ ['Settlement Date', DateHelper::getDateValue('01-Jan-2011')], ['Maturity Date', DateHelper::getDateValue('25-Oct-2012')], ['Frequency', 4], ]; // Some basic formatting for the data $worksheet->fromArray($arguments, null, 'A1'); $worksheet->getStyle('B1:B2')->getNumberFormat()->setFormatCode('dd-mmm-yyyy'); // Now the formula $worksheet->setCellValue('B6', '=COUPDAYSNC(B1, B2, B3)'); $helper->log($worksheet->getCell('B6')->getValue()); $helper->log('COUPDAYSNC() Result is ' . $worksheet->getCell('B6')->getFormattedValue());