Found the following HTML validation problems:
Alelager.html:39:1: Warning: trimming empty <li>
Alelager.html:38:1: Warning: trimming empty <ul>
Bangladesh.html:42:1: Warning: trimming empty <li>
Bangladesh.html:41:1: Warning: trimming empty <ul>
Batters2005.html:39:1: Warning: trimming empty <li>
Batters2005.html:38:1: Warning: trimming empty <ul>
Beerwings.html:39:1: Warning: trimming empty <li>
Beerwings.html:38:1: Warning: trimming empty <ul>
BookPrices.html:40:1: Warning: trimming empty <li>
BookPrices.html:39:1: Warning: trimming empty <ul>
Bushmeat.html:39:1: Warning: trimming empty <li>
Bushmeat.html:38:1: Warning: trimming empty <ul>
Bushmeat2.html:39:1: Warning: trimming empty <li>
Bushmeat2.html:38:1: Warning: trimming empty <ul>
Cameras.html:39:1: Warning: trimming empty <li>
Cameras.html:38:1: Warning: trimming empty <ul>
Cereals.html:39:1: Warning: trimming empty <li>
Cereals.html:38:1: Warning: trimming empty <ul>
Challenger.html:39:1: Warning: trimming empty <li>
Challenger.html:38:1: Warning: trimming empty <ul>
ChiMarathonMen.html:39:1: Warning: trimming empty <li>
ChiMarathonMen.html:38:1: Warning: trimming empty <ul>
Cuckoos.html:39:1: Warning: trimming empty <li>
Cuckoos.html:38:1: Warning: trimming empty <ul>
Diving2017.html:39:1: Warning: trimming empty <li>
Diving2017.html:38:1: Warning: trimming empty <ul>
Fatalities.html:39:1: Warning: trimming empty <li>
Fatalities.html:38:1: Warning: trimming empty <ul>
FishMercury.html:39:1: Warning: trimming empty <li>
FishMercury.html:38:1: Warning: trimming empty <ul>
FlightDelays.html:39:1: Warning: trimming empty <li>
FlightDelays.html:38:1: Warning: trimming empty <ul>
GSS2002.html:39:1: Warning: trimming empty <li>
GSS2002.html:38:1: Warning: trimming empty <ul>
GSS2006.html:39:1: Warning: trimming empty <li>
GSS2006.html:38:1: Warning: trimming empty <ul>
Girls2004.html:39:1: Warning: trimming empty <li>
Girls2004.html:38:1: Warning: trimming empty <ul>
Groceries.html:39:1: Warning: trimming empty <li>
Groceries.html:38:1: Warning: trimming empty <ul>
ILBoys.html:39:1: Warning: trimming empty <li>
ILBoys.html:38:1: Warning: trimming empty <ul>
IceCream.html:39:1: Warning: trimming empty <li>
IceCream.html:38:1: Warning: trimming empty <ul>
Illiteracy.html:39:1: Warning: trimming empty <li>
Illiteracy.html:38:1: Warning: trimming empty <ul>
Lottery.html:39:1: Warning: trimming empty <li>
Lottery.html:38:1: Warning: trimming empty <ul>
MathAnxiety.html:39:1: Warning: trimming empty <li>
MathAnxiety.html:38:1: Warning: trimming empty <ul>
Maunaloa.html:39:1: Warning: trimming empty <li>
Maunaloa.html:38:1: Warning: trimming empty <ul>
MnGroundwater.html:39:1: Warning: trimming empty <li>
MnGroundwater.html:38:1: Warning: trimming empty <ul>
MobileAds.html:39:1: Warning: trimming empty <li>
MobileAds.html:38:1: Warning: trimming empty <ul>
NBA1617.html:39:1: Warning: trimming empty <li>
NBA1617.html:38:1: Warning: trimming empty <ul>
NCBirths2004.html:39:1: Warning: trimming empty <li>
NCBirths2004.html:38:1: Warning: trimming empty <ul>
Nasdaq.html:39:1: Warning: trimming empty <li>
Nasdaq.html:38:1: Warning: trimming empty <ul>
Olympics2012.html:39:1: Warning: trimming empty <li>
Olympics2012.html:38:1: Warning: trimming empty <ul>
Phillies2009.html:39:1: Warning: trimming empty <li>
Phillies2009.html:38:1: Warning: trimming empty <ul>
Pitchers2005.html:39:1: Warning: trimming empty <li>
Pitchers2005.html:38:1: Warning: trimming empty <ul>
Quakes.html:39:1: Warning: trimming empty <li>
Quakes.html:38:1: Warning: trimming empty <ul>
Quetzal.html:39:1: Warning: trimming empty <li>
Quetzal.html:38:1: Warning: trimming empty <ul>
RangersTwins2016.html:39:1: Warning: trimming empty <li>
RangersTwins2016.html:38:1: Warning: trimming empty <ul>
Reading.html:39:1: Warning: trimming empty <li>
Reading.html:38:1: Warning: trimming empty <ul>
Recidivism.html:39:1: Warning: trimming empty <li>
Recidivism.html:38:1: Warning: trimming empty <ul>
Salaries.html:39:1: Warning: trimming empty <li>
Salaries.html:38:1: Warning: trimming empty <ul>
Sat2008.html:39:1: Warning: trimming empty <li>
Sat2008.html:38:1: Warning: trimming empty <ul>
Service.html:39:1: Warning: trimming empty <li>
Service.html:38:1: Warning: trimming empty <ul>
Skateboard.html:39:1: Warning: trimming empty <li>
Skateboard.html:38:1: Warning: trimming empty <ul>
Skating2010.html:39:1: Warning: trimming empty <li>
Skating2010.html:38:1: Warning: trimming empty <ul>
Spruce.html:39:1: Warning: trimming empty <li>
Spruce.html:38:1: Warning: trimming empty <ul>
Starcraft.html:39:1: Warning: trimming empty <li>
Starcraft.html:38:1: Warning: trimming empty <ul>
TV.html:39:1: Warning: trimming empty <li>
TV.html:38:1: Warning: trimming empty <ul>
TXBirths2004.html:39:1: Warning: trimming empty <li>
TXBirths2004.html:38:1: Warning: trimming empty <ul>
Titanic.html:39:1: Warning: trimming empty <li>
Titanic.html:38:1: Warning: trimming empty <ul>
Turbine.html:39:1: Warning: trimming empty <li>
Turbine.html:38:1: Warning: trimming empty <ul>
Verizon.html:39:1: Warning: trimming empty <li>
Verizon.html:38:1: Warning: trimming empty <ul>
Volleyball2009.html:39:1: Warning: trimming empty <li>
Volleyball2009.html:38:1: Warning: trimming empty <ul>
Walleye.html:39:1: Warning: trimming empty <li>
Walleye.html:38:1: Warning: trimming empty <ul>
Watertable.html:39:1: Warning: trimming empty <li>
Watertable.html:38:1: Warning: trimming empty <ul>
corrExerciseA.html:39:1: Warning: trimming empty <li>
corrExerciseA.html:38:1: Warning: trimming empty <ul>
corrExerciseB.html:39:1: Warning: trimming empty <li>
corrExerciseB.html:38:1: Warning: trimming empty <ul>
manatees.html:39:1: Warning: trimming empty <li>
manatees.html:38:1: Warning: trimming empty <ul>
wafers.html:39:1: Warning: trimming empty <li>
wafers.html:38:1: Warning: trimming empty <ul>