Variables: 
Fib0 ( Low ), 
Fib236 ( ( ( High - Low ) * 0.236 + Low ) ) ,
Fib764 ( ( ( High - Low ) * 0.764 + Low ) ) , 
Fib100 ( High ) ; 

// reset on a date change
if Date <> Date[1] then 
begin 
	//reset the Fibonaaci Retracements to the first bar
	Fib0 = Low ; 
	Fib236 = ( ( High - Low ) * 0.236 + Low ) ; 
	Fib764 = ( ( High - Low ) * 0.764 + Low ) ;
	Fib100 = High ; 
end ; 

// update Fibonacci 0% Retracement
if Low < Fib0 then Fib0 = Low ;

 // update Fibonacci 100% Retracement
if High > Fib100 then Fib100 = High ;

// update Fibonacci 23.6% Retracement
if ( ( Fib100 - Fib0 ) * 0.236 + Fib0 ) < Fib236 then Fib236 = ( ( Fib100 - Fib0 ) * 0.236 + Fib0 ) ;

// update Fibonacci 76.4% Retracement
if ( ( Fib100 - Fib0 ) * 0.764 + Fib0 ) > Fib764 then Fib764 = ( ( Fib100 - Fib0 ) * 0.764 + Fib0 ) ;

// plot Fibonacci Retracements on the chart
Plot4 ( Fib100, "100%", Red ) ; 
Plot3 ( Fib764, "76.4%", Darkgray ) ;
Plot2 ( Fib236, "23.6%", Darkgray ) ; 
Plot1 ( Fib0, "0%", Red ) ;