In Estate of Murphy (1976) 15 Cal.3d 907, the California Supreme Court announced the principle that this presumption is one that affects the burden of proof, with the consequence that the burden is on the party asserting its separate character to rebut the presumed fact that the property is held as community property by a preponderance of the evidence. The Murphy court, supra, stated that, generally speaking, there are two methods for a party to rebut this community property presumption by carrying the burden of proving that the property is separate property rather than community in nature. One method is by directly tracing the asset to a separate property source. The second method most commonly seen is the presentation of proof that, at the time of acquisition of the property by a married couple, all community income was exhausted by family expenses.