GB2139152A - Graphing aids - Google Patents

Abstract

A sheet of graph paper has one set of lines, M, of varying slope, the slope varying in accordance with a calculated statistic over a specified period of time. The money lines M of the inflation graph paper slope downwardly proportionately to the instantaneous rate of inflation. The assets of a Company may be plotted on the paper, the slope of the plotted line therefore representing the rate of increase or decrease of the value in real terms of those assets. <IMAGE>

Description

SPECIFICATION Graphing aids This invention relates to graphing aids. A "graphing aid" is hereby defined for the purposes of this application as being a sheet of writing material bearing two families of intersecting lines as an aid to the plotting of a graph on the sheet (for example, graph paper), or a sheet of translucent material to be used as an overlay for a graph and bearing two families of intersecting lines as an aid to interpretation of the graph.

In order to show the financial growth, or otherwise, or an enterprise, it is common practice to plot a graph showing the value of some monetary measure, such as profit, year by year over a period. An example is shown in Figure 1 of the accompanying drawings, which is a graph showing the assets of a building society for the period 1972 to 1982. However, it is well known that prices and wages in general have tended to rise year by year in the recent past, more than can be explained by genuine changes in costs or rewards. This is known as 'inflation', and has also been interpreted as a decline in the value of money. This means that a graph of the type shown in Figure 1 can be misleading, because an enterprise that in real terms is standing still, will appear from the graph to be expanding, at a rate that really only reflects the general rise in wages and prices, or inflation.Expansion is exaggerated, and contraction is understated or presented as a slight expansion.

In accordance with the present invention, there is provided a graphing aid (as herein before defined) wherein the lines in one family are parallel and each represents a specified time, the spacing of each line in the other family from a datum axis perpendicular to the lines in said family varying so as to be a mathematical function of a calculated statistic which varies over the period of specified times.

In the case where the lines in said other family are each to represent a particular sum of money, the spacing of each line in said other family from the datum axis may vary so as to be a graphing aid as claimed in claim 1, and wherein the lines in the other family are each to represent a particular sum of money, the spacing of each line in said other family from the datum axis varying so as to be a mathematical function of the value of that sum of money (as hereinbefore defined) over the period of specified times.

The "value" of a sum of money on a specified data is hereby defined for the purposes of this specification as being the value of that sum of money on a datum date as modified by the effect of inflation between the datum date and the specified date. Therefore, if the rate of inflation between 1stJanuary 1982 and 1st January1983 were 10% per annum, and if the datum date is taken as 1stJanuary 1982, the value of 10 on istJanuaryl983wouldbe10x1001(100+ 10) =9.09.

A specific embodiment of the present invention will now be described by way of example with reference to the Figures 2 and 3 of the accompanying drawings, in which Figure 2 illustrates the construction of a sheet of graph paper according to the present invention, and Figure 3 is the graph of Figure 1 plotted on graph paper according to the present invention.

The general level of wages or prices is analysed, and the results published monthly, by the Department of Employment, in the form of a set of index figures relating the current levels of various measures to their levels at a datum date. The best known measure is the Retail Prices Index, for which the index figure was 100 on 15th January 1974, and this index is chosen as the measure of inflation in the specific embodiment described herein with reference to Figures 2 and 3.

The construction of the graph paper of Figure 2 is as follows. The horizontal axis H, representing 0 is equally divided, and vertical lines T extend upwardly from the divisions. Each vertical line T represents a new year, and the years are marked along the axis H. The line Tfor 1stJanuary 1971 is used in this example as the vertical axis V and is equally divided by divisions D. Lines M extend to the right from each division, with the spacing d of each line from the axis H varying.For example, the spacing d(3;1977) of the 3 line above the axis H on 1 st January 1977 is equal to the spacing d(3;1971) of the 3 line above the axis H on 1st January 1971 multiplied by the Retails Price Index figure for 1stJanuary 1971, Rip1(1971, and divided by the index figure for 1stJanuary 1977, Rip1(1977). Since the axis V is equally divided, it will be noted that, for example, the spacing d(6;1977) of the 6 line above the axis H on 1st January 1977 is twice the spacing d(3;1977).In general, once one point for a sum Po at a time to has been plotted having a spacing d(Po;to) from the axis H, then the spacings d(p;t) of any other point will be given by the equation: d(p,t) = d(Po,to) x > c RPl(to) P0 d(Po,fo) x-P, RPl(t) To keep the graph a manageable size, it will be noted that the lines M for 8 to 38 do not extend to the left as far as the axis V.

To facilitate plotting, sufficient lines M should be printed on the paper. In addition to the lines M shown in Figure 2, further lighter lines may be printed between the lines M so that the vertical spacing of the lines is, for example, notgreaterthan Smm.

Thus, all the lines M used for plotting the height of the graph, instead of being horizontal as on conventional graph paper, slope proportionally downwards by greater or lesser amounts from year to year, reflecting the greater or lesser decline in the value of money at that time. In periods of nil inflation, the lines Mould have horizontal portions, and in periods of negative inflation, they would have upwardly sloping portions.

The graph paper can only be used for the particular years and particular currency for which it has been prepared. The 'factual' part of the graph paper would normally only extend as far forward in time as the last published index figure. However the paper can be tentatively extrapolated into the future. if probable future inflation rates are assumed, as shown in Figure 2 for the years 1983 to 1985.

The user may choose his own scale factor for labelling the lines M but must adhere to the prepared zero position i.e with the axis H representing 0, the lines M may be labelled from 0 to 38 or from 0 to 190, but not from 100to 290, for which a specially prepared piece of graph paper would be required, with the lines M dropping through the axis H instead of being asymptotic to it (assuming no negative inflation).

Figure 3 shows the graph of Figure 1 plotted on the graph paper of Figure 2. Whilst the graph of Figure 1 is likely to give at least a first impression that the assets are growing substantially, Figure 3 provides a more realistic impression of how the value of the assets has changed.

Interpolation between the guidelines is done vertically, not at right angles to the lines.

Means may be provided to enable the corrected figures to be read off within the accuracy possible; for instance faint horizontal lines scaled to the money value of a given date, or an overlay of similar design, or a scale rule, may be provided. To the right of Figure 3, scale is given of value based on the date 1st January 1982.

Special graph paper could be prepared showing combined corrections, for example for foreig n-tour operators, paper could be used reflecting the local currency rate to the , as well as the 'home' value of the .

Also, logarithmic graph paper may be produced, where the money scale is logarithmic.

The invention also applies to graph overlays comprising a sheet of transparent material marked with the two families of lines. However, in this case, the money lines M rise (assuming that the rate of inflation is positive). The corresponding equation for the points making up the lines M on the graph overlay is as follows.

d(p,tl=d(Po, P P x RPl(t) Po RPl(t0) The sheet is layed over a graph plotted on conventional right-angled graph paper, and the line of the graph is compared with the lines on the overlay.

Graphing aids for uses other than financial uses may be produced. For example, the vertical lines T may represent the months of the year and the lines M may represent levels of demand for heating oil over the year, the spacing of each line M from the axis varying over the year so as to be inversely proportional to demand for heating oil over the year. An oil supplier can then plot his weekly deliveries on the graph and be able to see at a glance whether his deliveries are increasing or declining relative to the normal for the time of year.

Claims (6)

1. A graphing aid (as hereinbefore defined) wherein the lines in one family are parallel and each represent a specified time, the spacing of each line in the other family from a datum axis perpendicular to the lines in said one family varying so as to be a mathematical function of a calculated statistic which varies over the period of specified times.

2. A graphing aid as claimed in claim 1, and wherein the lines in the other family are each to represent a particular sum of money, the spacing of each line in said other family from the datum axis varying so as to be a mathematical function of the value of that sum of money (as hereinbefore defined) over the period of specified times.

3. A graphing aid as claimed in Claim 2, wherein the aid is in the form of a sheet of writing material for plotting graphs, said spacings being proportional to said values, or porportional to the logarithm of said values.

4. A graphing aid as claimed in Claim 3, wherein the aid is in the form of a translucent graph overlay, said spacings being inversely proportional to said values or proportional to the logarithm of the reciprocal of said values.

5. A graphing aid, wherein said spacings decrease or increase over the period of specified times in accordance with the increases or decreases, as appropriate, of the Retail Price Index, or a like index.

New claims or amendments to claims filed on 16th March 1984 Superseded claims New or amended claims:

6. A graphing aid substantially as herein before described with reference to and as illustrated in Figures 2 and 3 of the accompanying drawings.