US economy shows solid GDP growth

Recent research shows that, the US economy has grown more than expected, expanding at an annual rate of 3.8% in the last quarter of 2004. The gross domestic product figure was ahead of the 3.1% the government estimated a month ago. Growth was at an annual rate of 4% in the third quarter of 2004 and for the year it came in at 4.4%, the best figure in five years. In the January-to-March quarter, the economy is expected to grow at an annual rate of about 4%, economists forecast. In the final quarter of 2004, businesses increased spending on capital equipment and software by 18%, up from 17.5% in the third quarter.
But as i read from one post last 2,3 week that there were some companies in Marietta closed and cause many people here lost their jobs. Diffrent from the US economy, Marietta economy is not on the way to grow "more than expected" with the fact that some companies here are not doing well.
Is it seems like an old city or an old company has less comparative advantage in produce products? And is this mean that the US economy is effected mainly just by those big cities and companies? what do you think?