$par
[1] 1969.0000000 1973.8448418 2015.5059550 2093.7051360    0.5806431

$objective
[1] 9.636249

$convergence
[1] 1

$iterations
[1] 99

$evaluations
function gradient 
     166      602 

$message
[1] "false convergence (8)"

