Pe -- expected price

Pe in the future D today
Pe in the future D today

Pog -- price of other goods

1) substitute goods

IF: P Maxwell House coffee D Folgers coffee

If: P of one product D of its substitute

2) complementary goods

P of wieners D of buns

P of one product D of its compliment

I -- income

1) normal goods

Income D for normal goods
Income D for normal goods

2) inferior goods

Income D for inferior goods
Income D for inferior goods

Npot -- number of POTENTIAL consumers

Npot D
Npot D

T -- tastes and preferences

Tastes for a product D for that product
Tastes for a product D for that product 

Pe -- expected price

Pe in the future S today
Pe in the future S today

Pog -- price of other goods ALSO PRODUCED BY THE FIRM

P soybeans S corn
P soybeans S corn

Pres -- price of resources

P autoworkers wages costs of producing cars S cars

Pres costs S
Pres costs S

Tech --technology

Improved technology costs S

Tax --taxes and subsidies

Taxes costs S
Taxes costs S

Subsidies costs S
Subsidies costs S

N -- number of producers/sellers

Nprod S
Nprod S