Variable

Theoretical Basis

Expected signs

Symbols

Data Source

Aggregate Business Investment

Dobrinsky [46] ; Verma [36]

no sign

(INVt)

World Development Indicator, 2017; CBN Statistical Bulletin, 2017 [47] [48]

Nation savings

Dobrinsky [46] ; Verma [36]

+

(SAVt)

World Development Indicator, 2017; CBN Statistical Bulletin, 2017 [47] [48]

Capital flow

Dobrinsky [46]

±

(CFt)

World Development Indicator (WDI), 2017; CBN Statistical Bulletin, 2017 [47] [48]

Level of monetization

Feldstein and Horioka [38] ; Kaya [37]

±

(LMt)

World Development Indicator, 2017; CBN Statistical Bulletin, 2017 [47] [48]

Financial Development Efficiency

Feldstein and Horioka [38] ; Dobrinsky [46] ; Verma [36]

+

(FEDt)

World Development Indicator, 2017; CBN Statistical Bulletin, 2017 [47] [48]