Adding values of strings containing a specific string in Javascript

I have an object called guild, that has the following array:

members: [
{
uuid: "6afc724d566746c796d13b233c9960ea",
rank: "MEMBER",
joined: 1492733608170,
dailyCoins-1-5-2017: 920,
dailyCoins-2-5-2017: 790,
dailyCoins-3-5-2017: 260,
dailyCoins-4-5-2017: 790
},
{
uuid: "fa014557f1ac4325b23940fb872031a4",
rank: "MEMBER",
joined: 1493332956351
},
etc.

How can I add together the value of each string that contains the string "dailyCoins" ?

Here is my current attempt:

 var guildMembers = [];
 var memberCoins = 0;
    for (i = 0; i < guild.members.length; i++) {
        for (j = 0; j < Object.keys(guild.members[i]).length; j++)
            console.log(Object.keys(guild.members[i]));
            if (Object.keys(guild.members[i])[j].includes("dailyCoins")) {
                var memberCoins = memberCoins + Object.values(guild.members[i])[j];
            }
        var member = {
            uuid: guild.members[i].uuid,
            rank: guild.members[i].rank,
            joined: guild.members[i].joined,
            coins: memberCoins
        };
        guildMembers.push(member);
    }

via builder_247