Quantitative data on any subject, usually collected with a purpose such as recording performance of bodies for comparison, or for public record and which can then be analysed by a variety of statistical methods. Statistics also refers to the study of collecting, analysing, and displaying such data, a discipline which has grown enormously since the start of the 20th century. Statistics might be seen as the reverse of probability; in probability, a random scenario or process is understood, and conclusions are made about data that might arise from that process while, with statistics, data have been collected and conclusions are drawn about the underlying random processes (see inference).