In 2015, LEGO released 6 Seasonal Christmas sets, all of these sets have been retired. For that year, the total price of all retail sets cost $28, today those sets are valued around $177, a growth of 533%.
Most valuable 2015 LEGO Seasonal Christmas set
40139 Gingerbread House $51.61
Highest growth 2015 Seasonal Christmas set
851358 Holiday Bauble White Bricks +284.98%
Theme / Subtheme Seasonal / Christmas
Year 2015
Pieces / Minifigs 107 / 2
Availability Retired
40124 LEGO Christmas Winter Fun
Retail $9.99
Value $16.15
Growth  +61.7%
Annual growth 5.6%
Theme / Subtheme Seasonal / Christmas
Year 2015
Pieces / Minifigs 167 / 1
Availability Retired
40125 LEGO Christmas Santa's Visit
Retail $9.99
Value $29.74
Growth  +197.7%
Annual growth 6.2%
Theme / Subtheme Seasonal / Christmas
Year 2015
Pieces 233
Availability Retired
40138 LEGO Christmas Train
promotional
Value $35.49
Annual growth 5.1%
Theme / Subtheme Seasonal / Christmas
Year 2015
Pieces 277
Availability Retired
40139 LEGO Christmas Gingerbread House
promotional
Value $51.61
Annual growth 8.1%
Theme / Subtheme Seasonal / Christmas
Year 2015
Pieces 62
Availability Retired
851358 LEGO Christmas Holiday Bauble White Bricks
Retail $7.99
Value $30.76
Growth  +285.0%
Annual growth 12.0%
Theme / Subtheme Seasonal / Christmas
Year 2015
Pieces 32
Availability Retired
5003083 LEGO Christmas Ornament
promotional
Value $13.23
Annual growth 6.1%