Variable Descriptions  Year Country Code (invariant) Country Label Area in Square Kilometers Area in  Square Miles Area of Empire in Square Miles²  Population  Population Density  Population of Empire²  Population Density of Empire²  Population, Cities of 100,000 & Over  Population, Cities of 100,000 & Over Per Capita  Population, Cities of 50,000 & Over  Population, Cities of 50,000 & Over Per Capita  Population, Cities of 25,000 & Over  Population, Cities of 25,000 & Over Per Capita  Population, Cities of 20,000 & Over  Population, Cities of 20,000 & Over Per Capita  Population, Cities of 10,000 & Over  Population, Cities of 10,000 & Over Per Capita  Nat'l Gov't Revenue & Expenditure³  Nat'l Gov't Revenue & Expenditure Per Capita³  Nat'l Gov't Revenue³  Nat'l Gov't Revenue Per Capita³  Nat'l Gov't Expenditure³ Nat'l Gov't Expenditure Per Capita³  Nat'l Defense Expenditure/Nat'l Gov't Expenditure  Imports³  Imports Per Capita³ Exports³  Exports Per Capita³  Proportion of World Trade  Energy Production, Metric Tons Coal Equivalent  Energy Production, Metric Tons Oil Equivalent Energy Production in Kilograms Coal Equivalent Per Capita  Energy Production in Kilograms Oil Equivalent Per Capita  Energy Consumption, Metric Tons Coal Equivalent  Energy Consumption, Metric Tons Oil Equivalent Energy Consumption in Kilograms Coal Equivalent Per Capita Energy Consumption in Kilograms Oil Equivalent Per Capita National Defense Expenditure³   National Defense Expenditure Per Capita³  Size of Military   Size of Military/Population  Percent GDP Originating in Industrial Activity Per Capita GDP Originating in Industrial Activity³  Percent Work Force in Agriculture  Percent Work in Industry  Percent Work Force in Other Activity  Railroad Mileage Railroad Mileage Per Square Mile Rail Passenger-Miles  Rail Passenger-Kilometers  Rail Ton-Miles  Rail Ton-Kilometers  Rail Ton-Mile Per Capita Passenger Cars  Passenger Cars Per Capita  Commercial Vehicles  Commercial Vehicles Per Capita  All Highway Vehicles  All Highway Vehicles Per Capita  All Telephones, including Cellular Mobile Cellular Telephones Telephones, excluding Cellular Telephones, excluding Cellular Per Capita Mobile Cellular Telephones Per Capita All Telephones, including Cellular, Per Capita Telegraph Mileage   Telegraph Mileage Per Square Mile  Telegrams  Telegrams Per Capita   First Class Mail  First Class Mail Per Capita  All Letter-Post Mail All Letter-Post Mail Per Capita Radios  Radios Per Capita  Televisions  Televisions Per Capita  Daily Newspaper Circulation Per Capita  Book Production by Titles Book Production by Titles Per Capita  Primary School Enrollment  Primary School Enrollment Per Capita  Secondary School Enrollment  Secondary School Enrollment Per Capita  Primary + Secondary School Enrollment  Primary + Secondary School Enrollment Per Capita Primary/Primary + Secondary School Enrollment  University Enrollment  University Enrollment Per Capita    All School Enrollment  All School Enrollment Per Capita  Percent Literate  Inhabitants Per Physician  Physicians Per Capita  National Income Per Capita³ Gross Domestic Product Per Capita (Factor Cost)³ Gross National Product Per Capita (Market Prices)³ Currency in Circulation Per Capita³  Age of Currency in Months Official/Principal Exchange Rate, Local Currency/ $US  Free/Black Market Rate, Local Currency Per $US  Assassinations General Strikes Guerrilla Warfare Government Crises Purges Riots Revolutions Anti-Government Demonstrations Weighted Conflict Index  Percent Voter Turnout, Legislature  Registered Voters  Registered Voters/Population  Votes Cast, Lower House of Legislature  Votes Cast, Lower House of Legislature/Population  Number of Seats, Largest Party in Legislature Size of Legislature (Lower House) Effectiveness of Legislature Competitiveness of Nominating Process Party Coalitions Party Legitimacy Size of Legislature/Number of Seats, Largest Party  Composite Index, Seven-Year Average Seven-Year Total Party Fractionalization Index Type of Regime Number of Coups d'etat Number of Major Constitutional Changes Head of State Premier Effective Executive (Type) Effective Executive (Selection) Degree of Parliamentary Responsibility Size of Cabinet Number of Major Cabinet Changes Changes in Effective Executive Legislative Effectiveness Legislative Selection Number of Legislative Elections Internet Hosts Internet Hosts Per Capita Internet Users Internet Users Per Capita Estimated Personal Computers Estimated Personal Computers Per Capita International Status Ranking International Status, Case Size International Status, Composite Score International Status, Composite Standardized Score International Status, Quintile International Status, Weighted Rank International Status, Weighted Status Ordering International Status, Weighted Quintile Electric Power Production (kwh)  Electric Power Production, Metric Tons Coal Equiv. Electric Power Production, Metric Tons Oil Equiv. Electric Power Production (kwh) Per Capita  Electric Power Production, Metric Tons Coal Equiv. Per C. Electric Power Production, Metric Tons Oil Equiv. Per C. Steel Production (metric tons)  Steel Production (metric tons) Per Capita  Cement Production (metric tons)  Cement Production (metric tons) Per Capita  THE FOLLOWING VARIABLES ARE ALL PERCENT ANNUAL CHANGE Population Population Density Population, Cities of 100,000 & Over Per Capita Population, Cities of 50,000 & Over Per Capita National Government Revenue Per Capita National Government Expenditure Per Capita Imports Per Capita  Exports Per Capita  First Class Mail Per Capita  Televisions Per Capita Railroad Mileage Per Square Mile All Highway Vehicles Per Capita Telegraph Mileage Per Square Mile Telegrams Per Capita Telephones Per Capita All Letter-Post Mail Per Capita Daily Newspaper Circulation Per Capita Primary School Enrollment Per Capita Secondary School Enrollment Per Capita Primary + Secondary School Enrollment Per Capita University Enrollment Per Capita Energy Production in Kilograms Per Capita Energy Consumption in Kilograms Per Capita Percent GDP Originating in Industrial Activity Per Capita GDP Originating in Industrial Activity Percent Work Force in Agriculture Percent Work Force in Industry Rail Passenger-Kilometers Radios Per Capita Percent Literate Physicians Per Capita Gross Domestic Product Per Capita Gross National Product Per Capita Currency in Circulation Per Capita Age of Currency in Months     ²Entered for 13 countries: Austria-Hungary, Belgium, France, Germany, Italy, Japan, Netherlands, Portugal, Russia, Spain, Turkey, United Kingdom, United States.    ³In US dollars.