I did my first all-grain yesterday. I have done a bunch of extracts and a couple of partial mashes prior. Everything went smoothly I got a 77% efficiency from the mash resulting in 4.85Gallons of 1.065 wort. I poured in some water to bring the total volume to 6.5 Gallons. I started to boil and 70min later after adding all my hops I cooled the 5 gallons of wort to 76 degrees and took a gravity reading. The gravity was 1.052. Did I boil off all that sugar (1.065 to 1.052)? Is this normal?