{
"years": [2010, 2011, 2012, 2013, 2014, 2015],
"indexes": [8.7, 4.5, 6.1, 6.5, 7.4, 4.9]
}
obj.years.reduce((acc, n, i) => {
if (2012 <= n && n <= 2014) {
for (const k in obj) {
(acc[k] = acc[k] || []).push(obj[k][i]);
}
}
return acc;
}, {})