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Local Food Calculator: Methodology and Formulae

Part I

Percentage Spent on Local Food (U) =

[[(j+k+l+m+o+p) + (q+r)*6 + t*12] + [(i*12 – (j+k+l+m+o+p) – ((q+r)*6) – (t*12))*0.10)]]/(i*12)

(10% of total spending minus local spending is added to account for the local content of other food purchased by the household.)

Average share spent on local food among survey takers (V) = AVG(u1, u2, …, un)

Part II

If X>1 and X!=∞, OUTPUT:

Spending $(a+b+c+d) on the local foods you chose contributes ___X___ times as much income to the local economy as spending $(e+f+g+h+aa+ab+ac+ad) on non-local and processed food.

X = (a*A+b*B+c*C+d*D) / (e*E+f*F+g*G+h*H + aa*AA+ab*AB+ac*AC+ad*AD)Y = [(a*A+b*B+c*C+d*D) – (e*E+f*F+g*G+h*H + aa*AA+ab*AB+ac*AC+ad*AD)]*12

Z = [(a*A’+b*B’+c*C’+d*D’) – (e*E’+f*F’+g*G’+h*H’ +aa*AA’+ab*AB’+ac*AC’+ad*AD’)]*)]*12

If X<=1 or X=∞, OUTPUT:

Looks like you’re doing as much as you can to support the local economy!  Encourage your friends to be local heroes, too.  If every household in Hampshire, Hampden and Franklin counties spent just $5 more on local food and $5 less on non-local food each month, $XX more local income would be generated per year and XX local jobs would be created.

VARIABLES DEFINED

a = additional $ spent on fresh, local vegetables

b = additional $ spent on fresh, local fruit

c = additional $ spent on local dairy and eggs

d = additional $ spent on local meat

e = decreased $ spent on frozen foods

f = decreased $ spent on canned fruits and vegetables

g = decreased $ spent on chips, cookies, crackers

h = decreased $ spent on breakfast cereals

aa = decreased $ spent on long-distance vegetables

ab = decreased $ spent on long-distance fruit

ac = decreased $ spent on long-distance dairy and eggs

ad = decreased $ spent on long-distance meat

i = $ spent on groceries in an average month

j = $ spent on vegetable and fruit CSA in the last year

k = $ spent on meat CSA in the last year

l = $ spent on dairy or egg CSA in the last year

m = $ spent on grain CSA in the last year

o = $ spent on whole farm CSA in the last year

p = $ spent on other (food) CSA in the last year

q = $ spent on farmers’ market purchases in an average summer month

r = $ spent on farmers’ market purchases in an average winter month

t = $ spent on food described as “local” from the grocery store in an average month

A-H and AA-AD = Value added when all 279,312 households in Hampshire, Hampden and Franklin counties (or all 2,632,757 households in MA) spend $1 in the food category associated with values a-h and aa-ad, respectively

A’-H’ and AA’=AD’ = Jobs added when all 279,312 households in Hampshire, Hampden and Franklin counties (or all 2,632,757 households in MA) spend $1 in the food category associated with values a-h and aa-respectively


Please contact CISA for permission to reproduce this calculator. If you’d like more information on how we developed the calculators please contact Kelly Coleman.

Special thanks to Anita Dancs, Department of Economics, Western New England University and Helen Scharber, School of Critical Social Inquiry, Hampshire College, who developed the calculator tool for CISA.

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