Personally, for me an integral part in technical development is economic calculations, that's for them I use this resource https://books.google.com.ua/books?id=GDBWBQAAQBAJ&pg=PA28&lpg=PA28&dq=technical+developments+are+economic+calculations&source = bl & ots = KMJ36kWrHU...
// Create a timer that will fire every second
var timer = new System.Timers.Timer (1000);
// Assign a handler that will fire on timeout
timer.Elapsed + = OnTimeout;
// The timer will always work
timer.AutoReset = true;
timer.Enabled = true;