Function trims values after being passed in another function

I would like have renderData() display the values from max. When I console.log(max) in calculateData() it displays all three maximum values from three JSON objects. However, when I return max in renderData() it only shows the first value. Why is this, and what can I do to make it display all three values instead of just one? Note: data is the json list of objects being passed. Thank you!

function calculateData(data) {

    for (i in data) {

        var arr = [];
        var max;
        var obj = data[i].tones;

        obj.map(function(item) {
            var data = item.score;
            arr.push(data);
        })

        max = arr.reduce(function(a, b) {
            return Math.max(a, b);
        })

        //Returns an array containing dominant [emotion_tone, language_tone, social_tone]
        return renderData(max);
    }

}

function renderData(max) {
    console.log(max);
};

via agomez