What is Statistics?

Nowadays, the word statistics is defined in the following two senses:
1) In Singular Sense and
2) In plural Sense

In Singular sense it is defined as the "Body of Methods" consisting Collection, Presentation, Analysis and interpretation of Numerical facts or Data.

In Plural sense, it is always defined as the "Aggregate of Numerical Facts". For example, statistics of prices, statistics of wages, statistics of weights, statistics of births and deaths, statistics of males and females, etc.

Aggregate of Numerical Facts are also called "Statistical Data."

Macro-Economics

Macro-economics, the other half of economics, is the study of the behavior of the economy as a whole. In other words, macroeconomics deals with total or big aggregates such as national income, output & employment, total consumption and the general level of price.

In the words of Boulding:
"Macroeconomics deals not with individual quantities as such but with the aggregates of these quantities, not with individual income but with the national income, not with individual prices but with the price level, not with individual outputs but with the national output."

Macro analysis is helpful in understanding the functioning of economic system because one individual's economic study is not helpful for framing any policy, hence whole economy's study and its analysis is important.