Adults are trading in their hunger for brains and thirst for blood this season in favor of a little witchcraft and some high-tech superhero shenanigans this year.

The costume change could be economically significant.

As Americans appear to be less excited about Halloween and less interested in gory postmortem costumes, it could mean they're more optimistic.

The most popular adult Halloween costumes for the last few years have been zombies and vampires. Some analysts in 2012 attributed the ghastly costume choice to a national empathy with the living dead after years of economic horror and persistently high unemployment figures.

Also in 2012, Americans spent a record $8 billion on Halloween, according to a National Retail Federation survey. With the exception of a small dip in Halloween spending in 2009, this is the first year in eight that Halloween spending dropped, according to the NRF, and it's still going to be almost 55% higher than it was in 2005.

Analysts speculated last year that people spent more on Halloween during the darkest economic days because Halloween allows people to escape their lives – something they really want to do when things are hardest.

Instead of lifelessly wandering the streets saying, "hire me," people painted their faces and stumbled around mumbling "brains" for a day and it made them feel better.

Less interest in escaping

Fewer people are celebrating Halloween this year – 158 million, down from the all-time survey high of 170 million reported by NRF in 2012.

They're spending less – $75.03 on average, down from $79.82 last year.

And they're reverting to traditional costumes – dressing as witches and Batman characters instead of zombies and vampires.

Perhaps as the bubbling cauldron of economic apprehension and woe that characterize the last several years settles to a simmer, Americans are looking to get back to tradition. Even the kids are choosing historically popular costumes and plan to dress as princesses, animals and Batman characters.

While it's possible the quieter Halloween season could be a good omen for the greater economy, which has seen slow but steady declines in unemployment and some positive news despite the recent government shutdown and threat of default, it's not great news for Halloween pop-up shops or online and traditional retailers like Target, Wal-Mart and others that supply the quick costumes, wigs, vampire teeth and fake blood that make the holiday a party.

The NRF was quick to console retailers. While sales are likely to be down this Halloween, they're not going to cripple the growing industry.

Consumers are still planning to spend about 54.7% more than they did back in 2005.

"Still one of the most beloved and anticipated consumer holidays, Halloween will be far from a bust this year," NRF President and CEO Matthew Shay said in a statement.

The NRF survey found that about 43.6% Americans plan to dress up for Halloween, spending a cumulative $2.6 billion to transform themselves and their children into witches and princesses.

Of course, some costumes will still trick and treat Halloween revelers this fall.

"While traditional favorites top the list this year, there's always the chance of seeing over-the-top, unique costumes on Halloween," Prosper Insights Consumer Insights Director Pam Goodfellow said in a statement. "Costumes with clear pop culture references that mimic hit TV show characters or celebrities could easily surprise us all." 

Vampires and zombies are still among the top five most popular costumes. And national unemployment in September was still greater than 7%.

Top Adult Costumes

Top Children's Costumes

Top Pet Costumes

1. Witch

1. Princess

1. Pumpkin

2. Batman character

2. Animal 

2. Hot dog

3. Vampire

3. Batman character

3. (T) Cat

4. Zombie

4. Action/super hero

3. (T) Devil

5. Pirate

5. Spider-Man

5. Witch

6. Action/superhero

6. Witch

6. Superman

7. Superman

7. Zombie

7. Dog

8. Dracula

8. Disney princess

8. Bowties/fancy collar

9. Cat

9. Superman

9. Bee

10. Scary costume/mask

10. Fairy

10. (T) Batman