3 "50

S LOO S OM

0 2000 4000 MOO 80OO ICtOOO I7M) M^OO (^ WIOO XtOOO 17000 NOOO lUOO NUMBER or WELLS

Joiei>h E PoRUc. "Eronomics of the Petroleum Industry. •■ March IQ.JO. The Chase National Bank of the City of New York. SCALE .6

B. Correlation Between Weighted Average Price of Crude Oil and (a) Nunnber of Dry Holes Drilled and (b) Number of Oil Wells Drilled. Data Are by Years, 1915 to 1935.

The relation between the average price of crude oil and the number of dryholes drilled may be used as an index of wildcatting. The relation between the average price of crude oil and the number of oil wells drilled may be used as an index of development effort.

Ill

Ill=l|l=l|l=l|l=l|l33,

Chapter 40 OGIVE AND LORENZ CHARTS

X he Ogive chart is also called a cumulative frequency curve. Its definition is as follows: a frequency distribution in which "more than" or "less than" data are presented. One scale of the grid represents percentages and the other scale represents "more than" or "less than" values.

NUMftER OF FAMILIES

90,000,000

20,000,000

10,000,000

NUMftER OF FAMILIES RECEIVIN6 INCOMES OVER SPECIFIED AMOUNTS

<Z

Rrdrawn from Advertising and Selling, January 1917

Number of Families Receiving Incomes Over Specified Amounts in the United States in 1916.

1. In reading the above chart the amount of the income is read by the scale at the

bottom of the diagram. The number of families is indicated by the scale at the left-hand side.