The from-to-chart is the most exact technique of the three. We can develop an efficiency that considers the importance of the parts. Multi-column process charts and string diagrams assume that each part is equal in importance. Part importance is described by the quantity moved within a certain time and the weight of each part. The from-to-chart is a matrix. The sequence of operations is written down the left side of the form and across the top. The vertical sequence of machines is the "FROM" side of the matrix. The horizontal sequence of the machines is the "TO" side of the matrix. 

Let us consider five different parts (#1, #2, #3, #4, #5) which travel from R (receiving) to S(Shipping) departments by following different routes. Between receiving and shipping, there are machines located at A, B, C, D, E and F. Our job is to find a layout which will reduce the travel time and increase the efficiency. We can make improvements by rearranging the flow.

To evaluate this alternative, penalty points are assigned to each move depending upon how far the move is away from the present location. For example, the move R to A is right next door, so we multiply that weight time 1 (one block). R to B is two blocks away, so we multiply the 18 in that block times two, three blocks away times three, and so on. The circled numbers are the penalty points. Below and to the left of the diagonal line indicates backtracking, so the penalty points are doubled.

Now look for clues for improvement. The highest penalty points are the best clues. For example, form F to A has a penalty point of 300. This means that F should be closer to R. A new layout change of sequence will change both the vertical and horizontal sequence. An improved layout as shown in the figure below will give an efficiency of: