Speedtest *may* not give accurate data. I've heard from multiple sources that major cell and cable carriers have partnered with major speed test sites to spice(spike) up figures to make customers believe that they are getting higher than actual speeds.
Here is my speed in a northwest suburb of Los Angeles: 5 mbps both up and down.
That is inflated figure, per my download tests. To obtain an accurate network speed, I downloaded several files ranging from 20 to 50 MB(s) from several sites. The actual download speed is about 2 mbps in my neck of the woods.
The formula is thus: size of file(mega bytes) x 8 bits* / time of download (seconds) = actual speed (mbps or kbps)
*One byte contains 8 bits.