<P> The French engineer Charles Joseph Minard was one of the first to use pie charts in 1858, in particular in maps . Minard's map, 1858 used pie charts to represent the cattle sent from all around France for consumption in Paris (1858). </P> <P> Playfair thought that pie charts were in need of a third dimension to add additional information . It has been said that Florence Nightingale invented it, though in fact she just popularised it and she was later assumed to have created it due to the obscurity of Playfair's creation . </P> <P> A 3d pie chart, or perspective pie chart, is used to give the chart a 3D look . Often used for aesthetic reasons, the third dimension does not improve the reading of the data; on the contrary, these plots are difficult to interpret because of the distorted effect of perspective associated with the third dimension . The use of superfluous dimensions not used to display the data of interest is discouraged for charts in general, not only for pie charts . </P> <P> A doughnut chart (also spelled donut) is a variant of the pie chart, with a blank center allowing for additional information about the data as a whole to be included . Doughnut charts are similar to pie charts in that their aim is to illustrate proportions . This type of circular graph can support multiple statistics at once and it provides a better data intensity ratio to standard pie charts . It does not have to contain information in the center . </P>

Where are pie charts used in real life