The California Demographics Unit (the state equivalent of the U.S. Census Bureau) today released fresh estimates of city and county populations. The data is a snapshot of the state as of Jan. 2010 and is organized in four Excel spreadsheets:

City / County Population Estimates -- January 1, 2009 and 2010 (shows 2009 population with provisional 2010 estimate, plus percent change).

Population Estimates for Cities, Counties and the State, 2001-2010, with 2000 Benchmark (shows annual estimates of population, plus the figures from the 2000 federal census).

Population and Housing Estimates for Cities, Counties and the State, 2001-2010, with 2000 Benchmark (shows annual estimates of households and housing units, plus breakdowns of housing by type: SFRs, apartments, mobile, etc.).

January 2010 City Population Ranked by Size, Numeric, and Percent Change (shows cities ranked by numeric and percent change between 2009-2010 and 2000-2010).

Some highlights: Between 2009-2010 California grew 1.0 percent to 38,648,090. Sacramento County grew 0.9 percent to 1,445,327. Sacramento City grew 1.0 percent to 486,489. The fastest growing county is the state is Sutter, 2.7 percent. The fast growing city is Colfax, 5.67 percent.

As a sequel to Friday's blog post about OpenSecrets.org, the government watchdog group that tracks national campaign donations by industry, I should mention Follow the Money, the web site that does similar analysis of state candidates. The non-partisan, nonprofit National Institute on Money in State Politics is the group behind the service. Its goal is to reveal "the influence of campaign money on state-level elections and public policy in all 50 states". As with OpenSecrets, Follow the Money provides an interactive database which allows you to slice donations to candidates and voter initiatives by specific industry categories and sub-categories.

Take for example health insurance. States are responsible for most of the regulation of carriers, so it's not surprising that a lot of campaign funding comes from insurers. According to the National Institute, four of the largest companies (Wellpoint, UnitedHealth Group, Aetna and Humana) distributed $8.7 million in 42 states from 2005-2008. So far in 2010, the health industry in general gave a total of $16.1 million dollars to state candidates, political committees and ballot measures (53.9 percent to Democrats, 43.8 percent to Republicans). In California this year, health businesses have donated a total of $4.2 million (60.5 percent to Democrats, 33.3 percent to Republicans).

If you're a fan of those real-time data monitors like the U.S. National Debt Clock or the World Population Clock, you're going to love this social media tracker:

With President Obama calling on Wall Street to stop fighting legislation that would reform the financial industry, it's a good time to profile a watch dog site that monitors the influence of the finance sector on Congress.

OpenSecrets.org, the online service of the Center for Responsive Politics, crunches federal data to break down money spent on lobbying and campaign donations by industry. On the lobbying side, annual spending in the so-called FIRE sector (finance, insurance and real estate) has risen dramatically in the past ten years. The overall total in 2009 was $463 million compared to $208 million in 1998. The commercial banking sub-category grew from $32.5 million to $50.4 million over the same period.

Campaign contributions are similarly analyzed by industry. So far in this 2010 election cycle, a total of $117 million has been donated from the FIRE sector (individuals and PACS). Democrats got 56 percent, Republicans 44 percent of the cash. Of that, commercial banks gave $8.6 million (46 to 54 percent in favor of Republican lawmakers).

Which members of the 111th Congress received the most money from finance and the banks? John McCain got the most FIRE money ($35.9 million), followed by John Kerry ($19.8 million). Commerical banks gave McCain $2.8 million and Kerry $1.7 million. You can see data for all the other members and sort them by sub-category with the interactive table.

Iceland's Eyjafjallajokull volcano certainly has gotten a lot media attention, what with the havoc it's caused in the European airline industry. But compared to other eruptions in history, this current one is pretty puny.

So how do scientists determine the overall ferocity of a volcanic event? They use a measurement akin to the earthquake Richter Scale. The Volcanic Explosivity Index is a 1 to 8 scale in which each number is ten times as intense as the preceding one. The VEP takes into account a variety of factors, including volume of material ejected, height, flow and duration. Mount St. Helens in 1980 measured a VEI of 5. Pinatubo in 1991 measured between 5 and 6. The massive eruption that formed Yellowstone 600,000 years ago is estimated at the top VEI of 8. In contrast, the current Icelandic event is coming in at 2 to 3.

Incidentally, the BBC web site has a simple, but elegant animated guide explaining the origin and development of volcanoes around the world. It's a good 5-minute introduction to the science.

With so many cars and people in California, you'd think this state would have the highest overall car insurance premiums. But that honor goes to Louisiana with an average annual premium of $2,510.87, according to a new national survey by Insure.com. California comes in at number five with an average cost of $1,774.41. What state has the cheapest rate? It's Maine with a measly $902.85.

The Insure.com survey also looks at the most expensive car models to insure. Naturally, the ultra-luxury cars top the list. Number one is the Porsche 911 Carrera GT2 (6-cylinder, 2-door coupe) costing an annual average of $2,943.78. The least expensive? Mazda Tribute I (2WD, 4-door utility) at $1,070.25.

This Insure.com web sites also provides an interactive database where you can see an average premium for a particular make, model and state. Or you can browse by vehicle type (cars, trucks, SUVs, etc.). Bear in mind this survey is based on a hypothetical driver: 40-year-old male who commutes 12 miles to work. 

Today is the last day for U.S. residents to mail in their 2010 census forms without running the risk of being visited by a Census worker next month. The government estimates a savings of "about $85 million in operational costs for every percentage point increase in the national mail response rate." So the Census Bureau is pushing hard this year to boost participation rates. It even encourages civic leaders and regular people to track participation with an online map showing the current mail rate for places, counties and states.

Nationally, 68 percent have returned their questionnaires so far. That's a drop from 72 percent in 2000. Locally, the rates tends to parallel the state (66 percent in 2010, 73 percent in 2000). Urban centers like Sacramento County (69 percent, 74 percent) and Sacramento City (67 percent, 70 percent) run higher than nearby rural areas. For example, Sierra County (42 percent, 49 percent) shows a typically low response rate. Little Alpine County is the lowest in the state with 21 percent (but had 67 percent in 2000, go figure).

With news of the latest big earthquake -- this one in central China -- many people are wondering if there is more shaking happening in the world than is usual. A Los Angeles Times essay says no. The number of tremors, large and small, this year is rather typical. What may be different is the greater incidence of destructive quakes in populated areas. Most sesmic activity occurs in remote areas, but with expanding world population the chance of fatalities and severe damage increases.

For the obsessive worrier, the U.S. Geologic Survey provides near real-time reporting of recent earthquakes around the globe. Here's a running list of quakes (2.5 or greater in the United States and 4.5 or greater outside the country) that have occured in the past seven days. There's also a similiar list and accompanying map for current activity in California (magnitude 3.0 and greater). Map pinpoints are coded for recency and size.

Gov. Schwarzenegger's proposed 2010-11 budget contains a number of cuts in state spending on education and social services. The non-partisan California Budget Project recently issued a series of fact sheets that estimate the impact of these reductions on local schools and welfare programs (including Healthy Families, CalWORKS, In-Home Supportive Services and senior disability assistance). 

Three new CPB fact sheets calcuate the impact of the proposed $2.7 billion cut in K-12 education spending on counties, county offices of education and individual school districts. Each document estimates the total reduction in funding, as well as the estimated reduction per student. Sacramento County, for example, would lose $67.6 million or $322 per student. Sacramento City Unified School District would lose $12.8 million or $304 per student.

You don't have to be a total transportation wonk to find something of interest in the Traffic Safety Legislation Tracking Database, a partnership of the National Council of State Legislatures and the National Highway Traffic Safety Administration. The database is intended to provide up-to-date status on bills and chaptered laws introduced in the 50 states and District of Columbia. It covers 2007 thru 2010 legislation, which you can search by state, topic, keyword, year, status or sponsor.

The broad topic list includes: aggressive, distracted and impaired driving; school bus, motorcycle, bicycle and pedestrian safety; senior and teen drivers; speed limits and other critical issues. With this online database you can quickly see which states have laws prohibiting, say, texting while driving. Or using cell phones. Pretty handy when you're travelling out of state.

Caption: New driver Brandi Eadie, 16, looks down at her cell phone to read a text message as she drives through a rubber-cone course in Seattle on Wednesday, Jan. 6, 2010 to demonstrate the dangers of phone use while driving. (AP Photo/ Elaine Thompson)

The Bee's data reporter Phillip Reese has come up with another nifty interactive database. This one produces Sacramento weather conditions for any day between Jan. 1, 1911 and Feb. 28, 2010. Just enter a date and you'll easily see the high and low temperatures, plus any precipitation (in inches) for that day. Normally this sort of research requires one to browse through reels of Bee micorfilm at the public library, so the online database is a real time-saver.

If you need weather data more current than February, see the Sacramento history page on the Weather Underground site. (Weather Underground is the source of The Bee's weather page information.) Here you'll be able to retrieve city climate data from 1941 through the present. And if you're looking for historic weather records covering temperature, rainfall, wind, storms, etc., NOAA has collected these in a free online document: Climate of Sacramento, California (revised in June 2005).

Google recently released a cleaner version of its public transit maps database, which has grown to more than 450 cities worldwide.

Google Transit provides step-by-step directions for public transportation similar to what it does for travel by personal vehicle. You type in a starting address and destination, plus the date and time you want to leave. Google then tells you where and when to connect with buses and trains to reach your goal.

Northern California cities are pretty well represented in Google Transit. You'll find detailed maps for the Bay Area, Santa Cruz, Stockton, Santa Rosa, Redding and Rio Vista. The Sacramento region is covered, too, with mapping for Regional Transit, Roseville Transit, Unitrans and Yolobus.

It's spring break season. A good time for data guys to kick back and enjoy some of the terrific music available on the Web. You probably know about free streaming services like Pandora, Live365 and AccuRadio that let you listen to specific genres and customize your own channels of music. But I bet you don't know about Wolfgang's Vault, a site that specializes in recordings of live concerts from the past, mostly from the 60s and 70s.

This growing collection includes classic performances of top bands from a variety of genres. It's a real trip down memory lane. Here are just a few of the great featured musicians:

Rock: The Rolling Stones, Fleetwood Mac, Bruce Springsteen, The Grateful Dead 
Folk: Joan Baez, Bob Dylan, James Taylor, Gordon Lightfoot, Leonard Cohen
Country: Merel Haggard, The Oak Ridge Boys, Jimmy Webb, Dolly Parton
Jazz: Miles Davis, Count Basie, Dave Brubeck, Louis Armstrong, Oscar Peterson
Blues: Willie Dixon, John Mayall, Bonnie Raitt, Buddy Guy, Stevie Ray Vaughn
R&B: Booker T., Tina Turner, The Pointer Sisters, Ray Charles, Earth, Wind & Fire

The recordings are searchable by band, venue, genre and time period. In addition to free audio streaming of classic concerts, Wolfgang's Vault also sells downloads of the music as well as posters and photography. There's an iPhone app, too.