How Do TV Sweeps Periods Work?

iStock/gaiamoments
iStock/gaiamoments

Television’s February sweeps period started Thursday and runs through March 2, so brace yourself for a slew of guest stars, wedding episodes, and other attention-grabbers. We all know that TV networks try to spike their ratings during sweeps, but how exactly does the system work? Why do networks care about these particular weeks in the first place? Let’s take a look at some sweeps questions.

© Bettmann/CORBIS

When did sweeps begin?

The idea of sweeps dates back to 1954. That year, ratings research juggernaut Nielsen began sending a sample of households around the country little diaries in which the family would record everything it watched on TV for a seven-day period. These diaries were then returned to Nielsen and used to estimate the size of shows’ audiences. Over time, the sweeps period got longer, and even though we still hear talk of “sweeps week,” the modern sweeps period actually lasts four weeks.

How did we end up with this system?

Blame our crummy collective handwriting.

When Nielsen began sending out the viewing diaries in 1954, it was apparent that taking the time to read and collate all of the data from thousands of handwritten diaries was a pretty epic task. To cut down on the workload, Nielsen decided it would only send out diaries for four-week periods four times a year. Viewers would get the diaries in February, May, July, and November, and the data collected in each survey could be used for the next three months.

Where did the name “sweeps” come from, then?

The name “sweeps” is another artifact of Nielsen’s early methodology. Collecting all of those diaries and recording the data was thorny task, so to simplify the process the company collected the seven-day diaries by region. Nielsen collected the Northeast’s diaries first and then “swept” across the country until it had the logs of West Coast viewers.

Do sweeps really “set the advertising rates” for the next quarter?

Yes and no. National ads make up the majority of networks’ advertising revenues; a typical half-hour primetime show will feature six minutes of national ads and just two minutes of local ads. Sweeps don’t affect the rates for national ads, which are set using year-round national data.

Sweeps do affect the rates for the two minutes of local ads, though. The month-long bonanza of stunt casting and very special episodes determines how much local advertisers will be shelling out to air their ads for the following three months. This system gives networks a huge financial incentive to cram every ratings-grabbing ploy they can into any sweeps period.

Is it just me, or does this system make zero sense?

It’s not just you. Back in the days when all of the viewing diaries were handwritten, the logistical hurdles of collecting the data made the sweeps system seem reasonable. Now that the process could be computerized, it makes much less sense. The system is somewhat akin to not eating for a week before weighing yourself then claiming the scale’s readout is your “real” weight.

Local advertisers loathe the sweeps system because it artificially inflates audience numbers, which in turn inflates the ad rates they have to pay. Networks and commission-based ad agencies love sweeps for just this reason, though. Since the local advertisers are mostly relatively small ad buyers in the grand scheme of things, they don’t have much leverage, so the sweeps system can continue to flourish.

Do people really still fill out paper diaries?

Yes. A 2004 piece by Sean Rocha in Slate estimated that Nielsen was still leafing through 1.6 million diaries each year. Nielsen has rolled out an automated alternative called the Local People Meter that can register audience information easily and more reliably. According to Nielsen’s website, the Local People Meters are already in place in the country’s largest media markets, and in 2007 the company announced plans to roll the LPM technology into 56 of the top 63 media markets. Theoretically, these meters could spell curtains for sweeps because they could easily and accurately estimate year-round audience sizes without the need for arbitrary sample periods like sweeps.

Take Advantage of Amazon's Early Black Friday Deals on Tech, Kitchen Appliances, and More

Amazon
Amazon

This article contains affiliate links to products selected by our editors. Mental Floss may receive a commission for purchases made through these links.

Even though Black Friday is still a few days away, Amazon is offering early deals on kitchen appliances, tech, video games, and plenty more. We will keep updating this page as sales come in, but for now, here are the best Amazon Black Friday sales to check out.

Kitchen

Instant Pot/Amazon

- Instant Pot Duo Plus 9-in-115 Quart Electric Pressure Cooker; $90 (save $40) 

- Le Creuset Enameled Cast Iron Signature Sauteuse 3.5 Quarts; $180 (save $120)

- KitchenAid KSMSFTA Sifter with Scale Attachment; $95 (save $75) 

- Keurig K-Mini Coffee Maker; $60 (save $20)

- Cuisinart Bread Maker; $88 (save $97)

- Anova Culinary Sous Vide Precision Cooker; $139 (save $60)

- Aicook Juicer Machine; $35 (save $15)

- JoyJolt Double Wall Insulated Espresso Mugs - Set of Two; $14 (save $10) 

- Longzon Silicone Stretch Lids - Set of 14; $13 (save $14)

HadinEEon Milk Frother; $37 (save $33)

Home Appliances

Roomba/Amazon

- iRobot Roomba 675 Robot Vacuum with Wi-Fi Connectivity; $179 (save $101)

- Fairywill Electric Toothbrush with Four Brush Heads; $19 (save $9)

- ASAKUKI 500ml Premium Essential Oil Diffuser; $22 (save $4)

- Facebook Portal Smart Video Calling 10 inch Touch Screen Display with Alexa; $129 (save $50)

- Bissell air320 Smart Air Purifier with HEPA and Carbon Filters; $280 (save $50)

Oscillating Quiet Cooling Fan Tower; $59 (save $31) 

TaoTronics PTC 1500W Fast Quiet Heating Ceramic Tower; $55 (save $10)

Vitamix 068051 FoodCycler 2 Liter Capacity; $300 (save $100)

AmazonBasics 8-Sheet Home Office Shredder; $33 (save $7)

Ring Video Doorbell; $70 (save $30) 

Video games

Sony

- Marvel's Spider-Man: Game of The Year Edition for PlayStation 4; $20 (save $20)

- Marvel's Avengers; $27 (save $33)

- Minecraft Dungeons Hero Edition for Nintendo Switch; $20 (save $10)

- The Last of Us Part II for PlayStation 4; $30 (save $30)

- LEGO Harry Potter: Collection; $15 (save $15)

- Ghost of Tsushima; $40 (save $20)

BioShock: The Collection; $20 (save $30)

The Sims 4; $20 (save $20)

God of War for PlayStation 4; $10 (save $10)

Days Gone for PlayStation 4; $20 (save $6)

Luigi's Mansion 3 for Nintendo Switch; $40 (save $20)

Computers and tablets

Microsoft/Amazon

- Apple MacBook Air 13 inches with 256 GB; $899 (save $100)

- New Apple MacBook Pro 16 inches with 512 GB; $2149 (save $250) 

- Samsung Chromebook 4 Chrome OS 11.6 inches with 32 GB; $210 (save $20) 

- Microsoft Surface Laptop 3 with 13.5 inch Touch-Screen; $1200 (save $400)

- Lenovo ThinkPad T490 Laptop; $889 (save $111)

- Amazon Fire HD 10 Tablet (64GB); $120 (save $70)

- Amazon Fire HD 10 Kids Edition Tablet (32 GB); $130 (save $70)

- Samsung Galaxy Tab A 8 inches with 32 GB; $100 (save $50)

Apple iPad Mini (64 GB); $379 (save $20)

- Apple iMac 27 inches with 256 GB; $1649 (save $150)

- Vankyo MatrixPad S2 Tablet; $120 (save $10)

Tech, gadgets, and TVs

Apple/Amazon

- Apple Watch Series 3 with GPS; $179 (save $20) 

- SAMSUNG 75-inch Class Crystal 4K Smart TV; $998 (save $200)

- Apple AirPods Pro; $169 (save $50)

- Nixplay 2K Smart Digital Picture Frame 9.7 Inch Silver; $238 (save $92)

- All-New Amazon Echo Dot with Clock and Alexa (4th Gen); $39 (save $21)

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- Anker Soundcore Upgraded Bluetooth Speaker; $22 (save $8)

- Amazon Fire TV Stick with Alexa Voice Remote; $28 (save $12)

Canon EOS M50 Mirrorless Camera with EF-M 15-45mm Lens; $549 (save $100)

DR. J Professional HI-04 Mini Projector; $93 (save $37)

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How Much Is the Earth Worth?

The New York Public Library, Unsplash
The New York Public Library, Unsplash

Our home planet may be the most precious place we know, but it isn't priceless. The Earth's resources and the value it offers to humans add up to some unknown, tangible cost. The species may never have to worry about buying or selling the world, but thinking of it in terms of concrete numbers can help us better understand its value. Now, as Treehugger reports, one scientist has developed a special formula that allows us to do just that.

According to the calculations of Greg Laughlin, an assistant astronomy and astrophysics professor from the University of California, Santa Cruz, the Earth is worth roughly $5 quadrillion (or $5,000,000,000,000,000). He came up with that price after gauging the planet's mass, temperature, age, and other factors that directly correlate to its ability to sustain life.

To emphasize just how valuable the Earth is, Laughlin also estimated the worth of other planets in our solar system. Our nearest neighbor Mars costs about the same as a used car at $16,000. That's a fortune compared to Venus, which he appraised at the meager value of one cent.

Laughlin doesn't expect these numbers to have applications in the real world. Rather, he hopes they will inspire people to better appreciate the only home they know. He's not the first person to put a massive, hypothetical price tag on something just for fun. The cost of the Death Star from Star Wars has been calculated at $852 quadrillion—many times Laughlin's estimate for Earth.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.