In 2007, the Land Forces consisted of 29,600 soldiers (6th Guards Mechanised Brigade (Grodno), 11th Guards Mechanized Brigade at Slonim, the 120th Guards Mechanised Brigade (Minsk), 38th and 103rd Mobile Brigades (organized similarly to Soviet airborne regiments, not all of them are equipped with BMD-1), 5th Spetsnaz Brigade (Maryina Horka), five artillery brigades and four regiments, two MRL regiments, 15th, 29th, 115th, 120th and 302nd SAM Brigades, two SSM brigades, two brigades and one regiment of engineers, 8th independent NBC Brigade, two signals brigades, 40th independent NBC battalion. Army equipment includes 1800 main battle tanks (MBT) and 2600 AFV/APC. The weapons and equipment storage bases include the 50th (Brest), 19th, 34th Tank Division & 37th Guards Tank Division (former tank divisions), 3rd Guards Tank Division, and 28th (Baranovichi). Weapons storage bases that have been disbanded include the 29th, 30th, 193rd Tank Division, and the storage base that used to be the 8th Guards Tank Division at Marina Gorka.
Question: How many more SAM brigades were there than SSM brigades?
Answer: 3