aggregate_hour:
    "function(doc) { 
        d = new Date(doc.date* 1000); 
        return {date:  Date.parse((d.getMonth() + 1) + '/' + d.getDate() + '/' + d.getFullYear() + ' ' + d.getHours() + ':00:00') / 1000}; 
     }"
     
aggregate_day:
    "function(doc) { 
        d = new Date(doc.date* 1000); 
        return {date:   Date.parse((d.getMonth() + 1) + '/' + d.getDate() + '/' + d.getFullYear()) / 1000}; 
     }"
    
aggregate_month:
    "function(doc) { 
    d = new Date(doc.date* 1000); 
    return {date:   Date.parse((d.getMonth() + 1) + '/1/' + d.getFullYear()) / 1000}; 
    }"