public function withDateAtStartOfYear() : self
    {
        $instance = $this->withTimeAtMidnight();
        
        $instance->date->setDate($instance->format('Y'), 1, 1);
        
        return $instance;
    }
public function withDateAtStartOfYear() : self
    {
        $instance = $this->withTimeAtMidnight();
        
        $instance->date->setDate($instance->format('Y'), 1, 1);
        
        return $instance;
    }
public function withDateAtStartOfYear ( ) : self { $ instance = $ this -> withTimeAtMidnight ( ) ; $ instance -> date -> setDate ( $ instance -> format ( 'Y' ) , 1 , 1 ) ; return $ instance ; }
Returns a new instance with the date set to 1st of Jan in the current year and time set to midnight.

@return self
Returns a new instance with the date set to 1st of Jan in the current year and time set to midnight .