(function loop(){
window.gem = window.gem || $(".header-market-link[href*=gem] .price-right").get()[0]
window.gdax = window.gdax || $(".header-market-link[href*=gdax] .price-right").get()[0]

let gemPrice = parseFloat(gem.innerText);
let gdaxPrice = parseFloat(gdax.innerText);
console.log(Math.round(gdaxPrice - gemPrice), Math.round(gemPrice/gdaxPrice * 1000) / 1000)
setTimeout(loop, 200)
})()