How to calculate maximum supported data rate of ATE Driver IC from voltage swing?

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Let us take example of MAX9957. Data rate can be calculated from TOC in datasheet as : 
 
 Figure 1: MAX9957 Driver 1 V, Signal Response Figure 2: RS and RL in DUT pin of MAX9957 
 (RL = 50 Ohm, VDHV = 0.5V and VDLV = 0V) is programmed then the output voltage will be 250mVpp. This 250mVpp (half of programmed VDH value=500mVpp) is seen because of the 50ohm source resistance and a 50ohm RL as shown in Figure 2. The output voltage becomes half of the actual set VDH voltage (voltage divider law). 
 That&rsquo;s why, even in above TOC: VDH is set to 1V, but actual swing is 500mVpp as shown in Figure 1. 
 Maximum data rate at any voltage can be calculated as &ndash; 
 =(Maximum data rate at 1V programmed VDHV) * (RL/RS+RL)/(our desired voltage)-----------1 
 Below are the steps to calculate data rate for this 
 - Typical Rise/Fall Time at 1V-programmed VDHV_, 20% to 80% = 130ps (From Electrical spec.) 
 - 20% to 80% is % of the edge so the &lsquo;full&rsquo; rising edge is about 130ps/0.6 = 216.67ps 
 - Full NRZ waveform would be two edges or 2 * 216.67ps = 433.33ps 
 - Maximum data rate at 1V-programmed VDHV_ = 1/ 433.333ps = 2.3Gbps 
 
 RS=RL= 50, Putting this formula in equation 1, we get, 
 =2.3Gbps *( (50/50+50) /0.25 
 = 2.3Gbps*0.5/0.25 
 =4.6Gbps)

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How to calculate maximum supported data rate of ATE Driver IC from voltage swing?

How to calculate maximum supported data rate of ATE Driver IC from voltage swing?