why this code doesn't work

[shermilden5000]

The variable "speed" should display the value of variable "ti" which is 0.00156. But it just displays some random number. Why this isn't working? any format conversion mismatch? double and inters etc? 

//+------------------------------------------------------------------+
//|                                                     trend101.mq4 |
//|                        Copyright 2017, MetaQuotes Software Corp. |
//|                                             https://www.mql5.com |
//+------------------------------------------------------------------+
#property copyright "Copyright 2017, MetaQuotes Software Corp."
#property link      "https://www.mql5.com"
#property version   "1.00"
#property strict
//+------------------------------------------------------------------+
//| Expert initialization function                                   |
//+------------------------------------------------------------------+

double speed = 0;
double ti = 0.00156;

void OnTick()
{

speed = ti;
Comment(StringFormat("Show prices\nSpeed = %d",speed));

 
}

[Carl Schreiber]

As %d is for int a double value isn't displayed - just use %f, like: %.5f

[William Roeder]

Or instead of hard coding precision (%0.5f) just use %s with
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