function[smm] = smmpsa(month,psa)
% SMMPSA PSA-benchmarked single month mortality rate
% INPUTS : month - month(s), n*1 vector
% psa - PSA factor
% OUTPUTS : smm - monthly SMM, n*1 vector
% EXAMPLE : smm(5,100), smm(1:30,150)
% AUTHOR : Dimitri Shvorob, dimitri.shvorob@vanderbilt.edu, 9/20/07
if ~isvector(month)
error('Input argument "month" must be a scalar or vector')
end
if any(month ~= floor(month) | month < 0)
error('Input argument "month" must contain non-negative integers')
end
if ~isscalar(psa) || psa < 0
error('Input argument "psa" must be a non-negative scalar')
end
i = ones(length(month),1);
j = min([i month(:)/30],[],2);
cpr = .0006*psa*j;
smm = 1 - (1-cpr).^(1/12);
